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Level II Challenges (158)

All challenges in Level II, ordered by date posted (the most recent appear first).

SIGABA CSP-889 — Part 2

[kopal-26] - 2 users already solved this challenge.
 
 
 

The SIGABA CSP-889 was a highly secure encryption machine used by the US for strategic communication in WWII. In this series of challenges, you are provided with a ciphertext and a partially-known plaintext, here with the length of 270 and 120 characters.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2021-06-01 13:35
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#2) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 1824 (242717) 2021-06-03 06:45:44
George Lasry (george4096) 1613 (399565) 2021-06-05 14:08:00
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SIGABA CSP-889 — Part 1

[kopal-25] - 2 users already solved this challenge.
 
 
 

The SIGABA CSP-889 was a highly secure encryption machine used by the US for strategic communication in WWII. In this series of challenges, you are provided with a ciphertext and a partially-known plaintext, here with the length of 320 and 120 characters.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2021-06-01 13:18
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#2) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 2000 (242717) 2021-06-02 10:40:32
George Lasry (george4096) 1725 (399565) 2021-06-03 22:50:04
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Wheatstone Cryptograph — Part 2

[madness-05] - 3 users already solved this challenge.
 
 
 

The Wheatstone Cryptograph is a simple device that resembles a clock with two hands. For each hand there is a ring of symbols. In this challenge the key is a random permutation of the english alphabet. Are you able to decrypt the given ciphertext?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2021-05-21 15:10
Maximum number of attempts for this challenge: 30

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Eugene (lim0n) 2000 (178540) 2021-05-21 19:56:41
Kurt Gebauer (Yokozuna) 2000 (282608) 2021-05-22 01:51:39
George Lasry (george4096) 1547 (399565) 2021-05-27 21:18:02
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The SZ42 Challenge — Part 11

[kopal-24] - 3 users already solved this challenge, 1 is working on it.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the eleventh challenge in a series of 13 level-2 challenges with the SZ42. In this "key breaking" challenge you are provided with one ciphertext and the corresponding plaintext. Can you find the wheel patterns?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2021-01-30 15:48
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

George Lasry (george4096) 1385 (399565) 2021-02-19 14:58:08
Kurt Gebauer (Yokozuna) 1307 (282608) 2021-03-11 11:39:16
Eugene (lim0n) 1269 (178540) 2021-04-01 08:15:04
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The SZ42 Challenge — Part 10

[kopal-23] - 3 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the tenth challenge in a series of 13 level-2 challenges with the SZ42. In this "key breaking" challenge you are provided with one ciphertext and the corresponding plaintext. Can you find the wheel patterns?
Update January 2021: The starting positions for the CHI wheels were added.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2021-01-30 15:40
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Eugene (lim0n) 2000 (178540) 2021-01-30 17:18:00
Kurt Gebauer (Yokozuna) 2000 (282608) 2021-01-30 17:40:00
George Lasry (george4096) 1660 (399565) 2021-02-02 19:40:00
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The SZ42 Challenge — Part 9

[kopal-22] - 4 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the ninth challenge in a series of 13 level-2 challenges with the SZ42. In this "setting" challenge you are provided with only one ciphertext; the patterns for all the wheels are known as well as the starting positions for the CHI wheels. Can you find the starting positions for both the MU and PSI wheels and decrypt the ciphertext?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-12-19 16:31
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#4) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2020-12-19 18:28:53
Eugene (lim0n) 2000 (178540) 2020-12-20 11:05:51
H. Lautenschlager (helmi) 1444 (56470) 2021-01-01 11:23:23
George Lasry (george4096) 1200 (399565) 2021-05-27 21:20:34
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The SZ42 Challenge — Part 8

[kopal-21] - 5 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the eighth challenge in a series of 13 level-2 challenges with the SZ42. In this "setting" challenge you are provided with only one ciphertext; the patterns for all the wheels are known as well as the starting positions for the CHI and PSI wheels. Can you find the starting positions for the MU wheels and decrypt the ciphertext?
Read more...

Click here to get to the corresponding forum topic to share your opinion.
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Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-10-31 16:06
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Eugene (lim0n) 2000 (178540) 2020-10-31 20:54:38
Kurt Gebauer (Yokozuna) 2000 (282608) 2020-10-31 21:34:32
H. Lautenschlager (helmi) 2000 (56470) 2020-11-01 00:38:54
Snake (snk) 1456 (187783) 2020-11-11 21:46:53
#5 George Lasry (george4096) 1373 (399565) 2020-11-21 17:53:47
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The SZ42 Challenge — Part 7

[kopal-20] - 4 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the seventh challenge in a series of 13 level-2 challenges with the SZ42. In this "setting" challenge you are provided with only one ciphertext; the patterns for all the wheels are known as well as the starting positions for the CHI and MU wheels. Can you find the starting positions for the PSI wheels and decrypt the ciphertext?
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-10-27 16:54
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#4) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2020-10-27 19:33:17
Eugene (lim0n) 2000 (178540) 2020-10-28 06:31:49
George Lasry (george4096) 1353 (399565) 2020-11-21 17:18:37
H. Lautenschlager (helmi) 1333 (56470) 2020-11-26 19:24:05
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The SZ42 Challenge — Part 6

[kopal-19] - 5 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the sixth challenge in a series of 13 level-2 challenges with the SZ42. In this "setting" challenge you are provided with only one ciphertext and the patterns for all five CHI wheels are known. Can you find the starting positions for the five CHI wheels?
Read more...

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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-10-02 20:09
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2020-10-02 21:03:47
Eugene (lim0n) 2000 (178540) 2020-10-03 14:07:02
Nicolas (nicosPavlov) 2000 (257791) 2020-10-03 16:38:41
H. Lautenschlager (helmi) 2000 (56470) 2020-10-03 17:00:18
#5 George Lasry (george4096) 1286 (399565) 2020-11-21 17:07:35
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The SZ42 Challenge — Part 5

[kopal-18] - 6 users already solved this challenge, 1 is working on it.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the fifth challenge in a series of 13 level-2 challenges with the SZ42. In this "setting" challenge you are provided with only one ciphertext and the patterns for CHI1 and CHI2 wheels are known. Can you find the starting positions for CHI1 and CHI2?
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-09-03 13:25
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#6) Achieved points (Global score) y-m-d - h:m:s

George Lasry (george4096) 2000 (399565) 2020-09-03 16:19:21
H. Lautenschlager (helmi) 2000 (56470) 2020-09-03 18:21:31
Eugene (lim0n) 2000 (178540) 2020-09-03 20:26:14
Nicolas (nicosPavlov) 2000 (257791) 2020-09-04 10:44:48
#5 Kurt Gebauer (Yokozuna) 2000 (282608) 2020-09-04 11:33:18
#6 Snake (snk) 1824 (187783) 2020-09-04 18:20:40
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The SZ42 Challenge — Part 4

[kopal-17] - 7 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the fourth challenge in a series of 13 level-2 challenges with the SZ42. In this "setting" challenge you are provided with only one ciphertext and the patterns for CHI1 and CHI2 wheels are known. Can you find the starting positions for CHI1 and CHI2?
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-08-29 23:25
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#7) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2020-08-30 00:14:50
Eugene (lim0n) 2000 (178540) 2020-08-30 12:42:34
H. Lautenschlager (helmi) 2000 (56470) 2020-08-30 12:53:38
George Lasry (george4096) 2000 (399565) 2020-08-30 17:19:16
#5 Armin Krauss (argh) 1725 (206965) 2020-09-01 21:57:52
#6 Nicolas (nicosPavlov) 1613 (257791) 2020-09-03 05:10:49
#7 Snake (snk) 1576 (187783) 2020-09-04 18:19:41
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The SZ42 Challenge — Part 3

[kopal-16] - 7 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the third challenge in a series of 13 level-2 challenges with the SZ42. Here, you are provided with 2 in-depth ciphertexts and a limitation is used. Can you recover the plaintexts?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-08-15 21:26
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#7) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2020-08-15 23:28:29
Nicolas (nicosPavlov) 2000 (257791) 2020-08-16 07:01:56
H. Lautenschlager (helmi) 2000 (56470) 2020-08-16 11:31:06
Eugene (lim0n) 2000 (178540) 2020-08-16 12:35:37
#5 Dominik M. (Sgt. Pepper) 2000 (128575) 2020-08-16 19:10:39
#6 Armin Krauss (argh) 1725 (206965) 2020-08-17 21:42:37
#7 George Lasry (george4096) 1576 (399565) 2020-08-21 21:02:59
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The SZ42 Challenge — Part 2

[kopal-15] - 9 users already solved this challenge.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the second challenge in a series of 13 level-2 challenges with the SZ42. Here, you are provided with 4 in-depth ciphertexts and a limitation is used. Can you recover the plaintexts?
Read more...

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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-08-05 15:44
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#9) Achieved points (Global score) y-m-d - h:m:s

George Lasry (george4096) 2000 (399565) 2020-08-05 17:05:39
Armin Krauss (argh) 2000 (206965) 2020-08-05 20:46:23
Eugene (lim0n) 2000 (178540) 2020-08-05 21:28:35
Dominik M. (Sgt. Pepper) 2000 (128575) 2020-08-05 23:18:08
#5 Kurt Gebauer (Yokozuna) 2000 (282608) 2020-08-05 23:56:11
#6 H. Lautenschlager (helmi) 1485 (56470) 2020-08-15 12:53:52
#7 Nicolas (nicosPavlov) 1485 (257791) 2020-08-15 15:15:41
#8 S Combes (jerva) 1292 (242717) 2020-09-20 20:55:34
#9 Random Dude (rnd) 1178 (103645) 2021-04-03 15:40:16
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The SZ42 Challenge — Part 1

[kopal-14] - 9 users already solved this challenge, 1 is working on it.
 
 
 

The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the first challenge in a series of 13 Level-2 challenges with the SZ42. Here, you are provided with 8 in-depth ciphertexts. Can you recover the plaintexts?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-07-22 23:20
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#9) Achieved points (Global score) y-m-d - h:m:s

Eugene (lim0n) 2000 (178540) 2020-07-23 16:28:56
Armin Krauss (argh) 2000 (206965) 2020-07-23 19:34:09
Dominik M. (Sgt. Pepper) 1613 (128575) 2020-07-27 14:04:16
Nicolas (nicosPavlov) 1576 (257791) 2020-07-28 11:57:43
#5 George Lasry (george4096) 1547 (399565) 2020-07-29 10:48:53
#6 Kurt Gebauer (Yokozuna) 1523 (282608) 2020-07-30 17:36:35
#7 H. Lautenschlager (helmi) 1373 (56470) 2020-08-13 20:47:47
#8 S Combes (jerva) 1270 (242717) 2020-09-20 10:56:05
#9 Random Dude (rnd) 1175 (103645) 2021-04-03 03:07:34
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Lightweight Introduction to Lattices — Part 3

[dimitrov-esslinger-03] - 24 users already solved this challenge.
 
 
 

This is part 3 of the challenge series about lattice-based cryptography schemes. This challenge introduces an encryption scheme which uses systems of linear equations. Can you decrypt a message without knowing the key?
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Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-07-16 12:58
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#24) Achieved points (Global score) y-m-d - h:m:s

Dominik M. (Sgt. Pepper) 2000 (128575) 2020-07-16 13:39:08
S (Zyphe) 2000 (13361) 2020-07-16 14:13:42
Kurt Gebauer (Yokozuna) 2000 (282608) 2020-07-16 14:34:01
H. Lautenschlager (helmi) 2000 (56470) 2020-07-16 14:42:10
#5 Snake (snk) 2000 (187783) 2020-07-16 15:07:38
#6 Viktor (Veselovský) 2000 (169444) 2020-07-16 22:00:42
#7 Eugene (lim0n) 2000 (178540) 2020-07-16 22:58:02
#8 Armin Krauss (argh) 2000 (206965) 2020-07-17 12:56:08
#9 Alain Collignon (vexilla72) 1824 (123666) 2020-07-17 18:39:14
#10 George (Theofanidis) 1824 (123216) 2020-07-17 19:54:10
#11 Silvia Kortmann (mikinsget) 1824 (20341) 2020-07-18 10:43:30
#12 Em Doulgerakis (Greko) 1725 (193799) 2020-07-19 11:13:43
#13 Nofre Tete (noffi) 1613 (26507) 2020-07-20 20:20:30
#14 DS (DS8279) 1576 (29732) 2020-07-22 12:14:13
#15 Derek Hatton (alfred_noble) 1406 (33998) 2020-08-01 17:46:10
#16 Marco Cinelli (Snap) 1324 (37769) 2020-08-18 16:34:40
#17 Tristan1473 (Tristan1473) 1315 (20432) 2020-08-22 12:53:25
#18 Polaris (Polaris) 1305 (32963) 2020-08-26 01:34:05
#19 Michael (FoM) 1201 (57794) 2020-12-21 03:51:15
#20 D3d4lu5 (D3d4lu5) 1198 (363488) 2020-12-29 19:46:17
#21 Gerd Wilts (gerdw) 1186 (50534) 2021-02-07 23:05:32
#22 Luigi Tomelli (archstanton) 1167 (127538) 2021-05-10 10:22:05
#23 Eric (ExAstris) 1166 (54941) 2021-05-17 03:53:50
#24 madness (madness) 1162 (71592) 2021-06-13 02:07:01
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Polyhomophonic Substitution — Part 3

[madness-03] - 14 users already solved this challenge.
 
 
 

This part of the challenge series introduces polyhomophonic substitution. In a polyhomophonic substitution cipher, each ciphertext symbol can represent one of several plaintext symbols, and each plaintext letter can be encrypted as one of several ciphertext letters. The key is a mapping from the set of plaintext symbols to the set of ciphertext symbols.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-04-06 20:44
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#14) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 2000 (206965) 2020-04-06 22:29:12
Snake (snk) 2000 (187783) 2020-04-07 08:54:32
Thomas (Thomas4897) 2000 (36141) 2020-04-07 14:25:54
Dominik M. (Sgt. Pepper) 2000 (128575) 2020-04-07 14:59:45
#5 Kurt Gebauer (Yokozuna) 2000 (282608) 2020-04-07 15:25:09
#6 Viktor (Veselovský) 2000 (169444) 2020-04-07 15:49:37
#7 J-L Morel (Rossignol) 1433 (42130) 2020-04-20 11:01:25
#8 D3d4lu5 (D3d4lu5) 1337 (363488) 2020-05-06 18:16:08
#9 George Lasry (george4096) 1310 (399565) 2020-05-14 23:52:33
#10 Norbert Biermann (Norbert) 1284 (47790) 2020-05-27 15:29:25
#11 Alain Collignon (vexilla72) 1199 (123666) 2020-09-16 08:49:49
#12 Michael (FoM) 1174 (57794) 2020-12-18 02:33:31
#13 Luigi Tomelli (archstanton) 1154 (127538) 2021-05-01 18:20:58
#14 Eric (ExAstris) 1151 (54941) 2021-05-29 19:54:05
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Polyhomophonic Substitution — Part 2

[madness-02] - 19 users already solved this challenge.
 
 
 

This part of the challenge series is a warm-up with polyphonic substitution. In a polyphonic substitution cipher, more than one plaintext letter are encrypted to the same ciphertext symbol. The key is a mapping from the set of plaintext symbols to the set of ciphertext symbols.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-03-28 15:09
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#19) Achieved points (Global score) y-m-d - h:m:s

Snake (snk) 2000 (187783) 2020-03-28 17:30:14
Armin Krauss (argh) 2000 (206965) 2020-03-28 22:07:46
Kurt Gebauer (Yokozuna) 2000 (282608) 2020-03-28 22:26:59
Alain Collignon (vexilla72) 2000 (123666) 2020-03-28 23:11:11
#5 Dominik M. (Sgt. Pepper) 2000 (128575) 2020-03-29 03:46:39
#6 J-L Morel (Rossignol) 2000 (42130) 2020-03-29 12:00:46
#7 Viktor (Veselovský) 2000 (169444) 2020-03-29 12:49:46
#8 Eugene (lim0n) 2000 (178540) 2020-03-29 14:49:22
#9 Thomas (Thomas4897) 1824 (36141) 2020-03-29 17:36:58
#10 sarah b (silva) 1824 (47847) 2020-03-29 21:05:46
#11 D3d4lu5 (D3d4lu5) 1307 (363488) 2020-05-06 18:15:02
#12 George Lasry (george4096) 1290 (399565) 2020-05-14 23:02:08
#13 Norbert Biermann (Norbert) 1270 (47790) 2020-05-26 19:48:41
#14 Nicolas (nicosPavlov) 1199 (257791) 2020-09-09 05:32:11
#15 Michael (FoM) 1173 (57794) 2020-12-14 13:48:24
#16 Em Doulgerakis (Greko) 1162 (193799) 2021-02-22 18:58:44
#17 Luigi Tomelli (archstanton) 1153 (127538) 2021-05-01 17:29:03
#18 Martin (martinbucher) 1152 (38365) 2021-05-15 17:14:36
#19 Eric (ExAstris) 1151 (54941) 2021-05-25 05:04:23
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The SIGABA Challenge — Part 2

[lasry-27] - 8 users already solved this challenge.
 
 
 

The SIGABA was a highly secure encryption machine used by the US for strategic communications in WWII. As in part 1 of this series of challenges, you are provided with a partial known-plaintext, and some information about the key settings. However, in this part you get less information about the key.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-03-05 19:44
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#8) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 2000 (242717) 2020-03-05 23:35:49
Kurt Gebauer (Yokozuna) 1576 (282608) 2020-03-11 11:19:06
Dominik M. (Sgt. Pepper) 1406 (128575) 2020-03-21 19:54:11
Snake (snk) 1406 (187783) 2020-03-21 21:49:15
#5 D3d4lu5 (D3d4lu5) 1378 (363488) 2020-03-26 17:57:45
#6 Nicolas (nicosPavlov) 1199 (257791) 2020-08-16 05:07:29
#7 Eugene (lim0n) 1190 (178540) 2020-09-10 22:24:09
#8 Em Doulgerakis (Greko) 1152 (193799) 2021-04-17 16:43:37
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The SIGABA Challenge — Part 1

[lasry-26] - 8 users already solved this challenge, 1 is working on it.
 
 
 

The SIGABA was a highly secure encryption machine used by the US for strategic communications in WWII. It is believed that the German codebreakers were unable to make any inroads against SIGABA. In this part of the series of challenges, you are provided with a partial known-plaintext, and some information about the key settings.
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Published on: 2020-02-29 12:29
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#8) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 2000 (242717) 2020-02-29 17:14:45
Dominik M. (Sgt. Pepper) 1576 (128575) 2020-03-06 02:41:04
Kurt Gebauer (Yokozuna) 1523 (282608) 2020-03-08 05:38:58
Snake (snk) 1373 (187783) 2020-03-21 14:15:47
#5 D3d4lu5 (D3d4lu5) 1349 (363488) 2020-03-26 17:55:38
#6 Nicolas (nicosPavlov) 1198 (257791) 2020-08-13 13:47:40
#7 Eugene (lim0n) 1190 (178540) 2020-09-06 18:11:16
#8 Em Doulgerakis (Greko) 1153 (193799) 2021-04-06 09:39:40
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The LoRa Cipher: Logic Randomness — Part 1

[theofanidis-10] - 19 users already solved this challenge.
 
 
 

LoRa calculates the ciphertext by using a logic expression as key. The ciphertext unusually contains large bitstreams too. Could you find the logic expression from a given ciphertext?
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Published on: 2020-02-19 20:31
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#19) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 2000 (169444) 2020-02-19 22:35:21
Kurt Gebauer (Yokozuna) 2000 (282608) 2020-02-20 02:32:51
Dominik M. (Sgt. Pepper) 2000 (128575) 2020-02-20 04:28:34
Eugene (lim0n) 2000 (178540) 2020-02-20 08:26:23
#5 Alain Collignon (vexilla72) 2000 (123666) 2020-02-20 08:50:23
#6 madness (madness) 2000 (71592) 2020-02-20 16:41:35
#7 Snake (snk) 2000 (187783) 2020-02-20 17:26:23
#8 Armin Krauss (argh) 2000 (206965) 2020-02-20 20:27:17
#9 Derek Hatton (alfred_noble) 1613 (33998) 2020-02-24 17:03:34
#10 Mir Dim (mir0soft) 1576 (79760) 2020-02-25 07:51:23
#11 pcback (langkhach11112) 1502 (4860) 2020-02-28 16:00:00
#12 H. Lautenschlager (helmi) 1444 (56470) 2020-03-03 18:52:35
#13 George Lasry (george4096) 1330 (399565) 2020-03-21 21:04:03
#14 sarah b (silva) 1327 (47847) 2020-03-23 08:49:21
#15 D3d4lu5 (D3d4lu5) 1244 (363488) 2020-05-12 23:50:49
#16 Marco Cinelli (Snap) 1230 (37769) 2020-05-30 15:17:23
#17 Em Doulgerakis (Greko) 1164 (193799) 2020-12-29 16:24:22
#18 Luigi Tomelli (archstanton) 1147 (127538) 2021-05-25 18:35:49
#19 Eric (ExAstris) 1147 (54941) 2021-05-26 03:14:48
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Differential Cryptanalysis — Part 2

[kopal-bender-02] - 3 users already solved this challenge.
 
 
 

This challenge series introduces in detail the handling of the differential cryptanalysis (DCA). In the first two challenges you have to decrypt encrypted images and enter the code shown in the images. The second challenge requires filtering.
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Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2020-01-28 15:22
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Eugene (lim0n) 2000 (178540) 2020-01-29 05:52:19
Dominik M. (Sgt. Pepper) 2000 (128575) 2020-01-29 11:13:43
Kurt Gebauer (Yokozuna) 1824 (282608) 2020-01-30 00:15:28
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Polyphonic Substitution Cipher — Part 2

[tomokiyo-03] - 17 users already solved this challenge.
 
 
 

This is part two of the two polyphonic cipher challenges, where again two or more plaintext letters correspond to one cipher symbol. Can you solve such a cipher?
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Published on: 2020-01-14 15:20
Maximum number of attempts for this challenge: 10

All successful users of this challenge

Rank User (#17) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2020-01-14 20:46:51
Snake (snk) 2000 (187783) 2020-01-14 21:48:19
Eugene (lim0n) 2000 (178540) 2020-01-15 11:18:08
George Lasry (george4096) 1824 (399565) 2020-01-16 00:47:13
#5 sarah b (silva) 1523 (47847) 2020-01-22 11:31:33
#6 George (Theofanidis) 1284 (123216) 2020-03-04 21:43:19
#7 madness (madness) 1281 (71592) 2020-03-07 13:38:01
#8 Thomas (Thomas4897) 1273 (36141) 2020-03-11 18:43:43
#9 Dominik M. (Sgt. Pepper) 1256 (128575) 2020-03-24 18:22:46
#10 Viktor (Veselovský) 1251 (169444) 2020-03-29 18:09:04
#11 D3d4lu5 (D3d4lu5) 1222 (363488) 2020-05-06 18:17:24
#12 Alain Collignon (vexilla72) 1177 (123666) 2020-09-14 01:19:07
#13 Martin (martinbucher) 1165 (38365) 2020-11-18 16:11:41
#14 Michael (FoM) 1161 (57794) 2020-12-12 23:30:41
#15 Em Doulgerakis (Greko) 1153 (193799) 2021-02-21 22:39:40
#16 Luigi Tomelli (archstanton) 1146 (127538) 2021-05-06 13:33:01
#17 Eric (ExAstris) 1144 (54941) 2021-05-24 00:45:44
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Christmas Challenge 2019: Differential Cryptanalysis — Part 1

[kopal-bender-01] - 3 users already solved this challenge.
 
 
 

This challenge series introduces in detail the handling of the differential cryptanalysis (DCA). In the first two challenges you have to decrypt encrypted images and enter the code shown in the images. The first challenge needs no filtering, as only valid plaintext-ciphertext pairs are delivered.
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Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-12-22 21:04
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Eugene (lim0n) 1660 (178540) 2019-12-26 16:31:43
Kurt Gebauer (Yokozuna) 1523 (282608) 2019-12-30 03:08:38
Dominik M. (Sgt. Pepper) 1456 (128575) 2020-01-03 18:30:14
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Polyphonic Substitution Cipher — Part 1

[tomokiyo-02] - 20 users already solved this challenge, 1 is working on it.
 
 
 

In a polyphonic cipher, two or more plaintext letters correspond to one ciphertext symbol.
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Published on: 2019-11-21 13:18
Maximum number of attempts for this challenge: 10

All successful users of this challenge

Rank User (#20) Achieved points (Global score) y-m-d - h:m:s

sarah b (silva) 2000 (47847) 2019-11-22 10:56:16
Bart den Hartog (Bart13) 1725 (148936) 2019-11-23 15:02:52
George Lasry (george4096) 1725 (399565) 2019-11-23 17:29:00
Snake (snk) 1725 (187783) 2019-11-23 21:47:29
#5 D3d4lu5 (D3d4lu5) 1725 (363488) 2019-11-23 22:47:12
#6 Kurt Gebauer (Yokozuna) 1547 (282608) 2019-11-28 02:28:03
#7 Eugene (lim0n) 1423 (178540) 2019-12-05 17:45:31
#8 Danny Higgins (hamster147) 1349 (39638) 2019-12-18 00:49:54
#9 Random Dude (rnd) 1337 (103645) 2019-12-20 18:42:25
#10 George (Theofanidis) 1229 (123216) 2020-03-01 20:01:11
#11 madness (madness) 1226 (71592) 2020-03-07 18:57:10
#12 Thomas (Thomas4897) 1223 (36141) 2020-03-11 18:24:02
#13 Dominik M. (Sgt. Pepper) 1216 (128575) 2020-03-24 17:35:47
#14 Viktor (Veselovský) 1213 (169444) 2020-03-30 00:37:50
#15 Alain Collignon (vexilla72) 1169 (123666) 2020-09-03 11:31:59
#16 Martin (martinbucher) 1164 (38365) 2020-10-03 09:21:08
#17 Michael (FoM) 1155 (57794) 2020-12-11 15:27:14
#18 Em Doulgerakis (Greko) 1147 (193799) 2021-02-21 13:18:25
#19 Luigi Tomelli (archstanton) 1141 (127538) 2021-05-03 18:39:04
#20 Eric (ExAstris) 1140 (54941) 2021-05-23 23:37:14
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Cipher ID — Part 1

[mistamp-01] - 15 users already solved this challenge, 6 are working on it.
 
 
 

Determine which type of classic cipher was used to generate each of 500 ciphertext messages. The ciphers used in this challenge are simple substitution, columnar transposition, Vigenère, Playfair, and Hill.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-11-19 12:00
Maximum number of attempts for this challenge: 20

All successful users of this challenge

Rank User (#15) Achieved points (Global score) y-m-d - h:m:s

Bart den Hartog (Bart13) 2000 (148936) 2019-11-19 13:05:00
Viktor (Veselovský) 2000 (169444) 2019-11-19 14:41:45
D3d4lu5 (D3d4lu5) 2000 (363488) 2019-11-20 00:40:59
Armin Krauss (argh) 2000 (206965) 2019-11-20 10:40:28
#5 Eugene (lim0n) 1725 (178540) 2019-11-21 17:34:47
#6 George Lasry (george4096) 1660 (399565) 2019-11-22 23:30:33
#7 Kurt Gebauer (Yokozuna) 1613 (282608) 2019-11-23 22:20:16
#8 Snake (snk) 1444 (187783) 2019-12-02 11:48:55
#9 sakis55555 sakis (sakis55555) 1252 (1352) 2020-02-02 00:25:04
#10 George (Theofanidis) 1252 (123216) 2020-02-02 08:21:12
#11 sarah b (silva) 1248 (47847) 2020-02-06 10:29:55
#12 madness (madness) 1230 (71592) 2020-02-27 23:03:53
#13 Mike (RogueRamblers) 1195 (75961) 2020-05-12 02:33:57
#14 Em Doulgerakis (Greko) 1153 (193799) 2020-12-27 11:28:04
#15 Random Dude (rnd) 1143 (103645) 2021-04-10 22:59:57
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A Cloaked Substitution Cipher — Part 2

[kallick-27] - 14 users already solved this challenge.
 
 
 

Like the MONOALPHABETIC SUBSTITUTION WITH CAMOUFLAGE series of challenges, this two-part challenge considers a modification of the classic simple substitution cipher achieved by randomly introducing decoy characters into the ciphertext in encryption which are then ignored in decryption. In part 2, the plaintext is first divided into two parts, then each part will be encrypted separately.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-25 19:26
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#14) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 2000 (363488) 2019-08-26 00:10:35
Viktor (Veselovský) 2000 (169444) 2019-08-26 01:43:23
Snake (snk) 2000 (187783) 2019-08-26 01:58:38
Eugene (lim0n) 2000 (178540) 2019-08-26 12:30:26
#5 Kurt Gebauer (Yokozuna) 2000 (282608) 2019-08-26 15:17:12
#6 George (Theofanidis) 1576 (123216) 2019-08-31 00:32:21
#7 Alain Collignon (vexilla72) 1523 (123666) 2019-09-02 11:16:49
#8 sarah b (silva) 1523 (47847) 2019-09-02 13:12:48
#9 Armin Krauss (argh) 1523 (206965) 2019-09-02 18:56:22
#10 Bart den Hartog (Bart13) 1502 (148936) 2019-09-03 08:22:15
#11 George Lasry (george4096) 1385 (399565) 2019-09-14 13:17:41
#12 Random Dude (rnd) 1290 (103645) 2019-10-12 06:28:34
#13 Em Doulgerakis (Greko) 1252 (193799) 2019-11-08 13:51:58
#14 madness (madness) 1192 (71592) 2020-02-25 00:03:25
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A Cloaked Substitution Cipher — Part 1

[kallick-26] - 15 users already solved this challenge.
 
 
 

Like the MONOALPHABETIC SUBSTITUTION WITH CAMOUFLAGE series of challenges, this two-part challenge considers a modification of the classic simple substitution cipher achieved by randomly introducing decoy characters into the ciphertext in encryption which are then ignored in decryption. In part 1, the cipher uses a key which devides the ciphertext alphabet into signal characters and noise characters.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-21 12:05
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#15) Achieved points (Global score) y-m-d - h:m:s

Snake (snk) 2000 (187783) 2019-08-21 19:03:44
D3d4lu5 (D3d4lu5) 2000 (363488) 2019-08-21 19:03:46
Michael Möller (michaelm) 2000 (253196) 2019-08-21 23:36:41
Eugene (lim0n) 1824 (178540) 2019-08-22 12:59:50
#5 Kurt Gebauer (Yokozuna) 1824 (282608) 2019-08-23 09:06:13
#6 Bart den Hartog (Bart13) 1725 (148936) 2019-08-24 00:59:12
#7 Viktor (Veselovský) 1660 (169444) 2019-08-24 17:35:25
#8 George (Theofanidis) 1660 (123216) 2019-08-24 19:27:39
#9 Armin Krauss (argh) 1576 (206965) 2019-08-26 16:24:17
#10 sarah b (silva) 1523 (47847) 2019-08-28 12:59:17
#11 Alain Collignon (vexilla72) 1444 (123666) 2019-09-02 15:05:22
#12 George Lasry (george4096) 1357 (399565) 2019-09-14 16:21:30
#13 Random Dude (rnd) 1286 (103645) 2019-10-10 02:25:14
#14 Em Doulgerakis (Greko) 1262 (193799) 2019-10-25 20:45:39
#15 madness (madness) 1193 (71592) 2020-02-19 04:28:42
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The T52 Sturgeon Challenge — Part 12

[lasry-25] - 7 users already solved this challenge, 1 is working on it.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from a T52ca ciphertext. The key is partially known. You are also provided with a crib.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:32
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#7) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 1660 (363488) 2019-08-14 16:54:59
Kurt Gebauer (Yokozuna) 1523 (282608) 2019-08-18 15:58:58
Michael Möller (michaelm) 1196 (253196) 2020-01-27 22:15:31
Snake (snk) 1181 (187783) 2020-03-23 23:23:18
#5 Nicolas (nicosPavlov) 1159 (257791) 2020-07-28 16:06:37
#6 S Combes (jerva) 1143 (242717) 2020-12-30 23:21:59
#7 Mike (RogueRamblers) 1132 (75961) 2021-06-21 01:26:25
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The T52 Sturgeon Challenge — Part 11

[lasry-24] - 7 users already solved this challenge, 1 is working on it.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from a T52c ciphertext. The key is partially known. You are also provided with a crib.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:32
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#7) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 1660 (363488) 2019-08-14 17:05:47
Kurt Gebauer (Yokozuna) 1523 (282608) 2019-08-18 15:58:07
Michael Möller (michaelm) 1197 (253196) 2020-01-26 10:12:37
Snake (snk) 1181 (187783) 2020-03-22 20:17:10
#5 Nicolas (nicosPavlov) 1159 (257791) 2020-07-29 03:02:52
#6 S Combes (jerva) 1143 (242717) 2020-12-30 16:24:32
#7 Mike (RogueRamblers) 1132 (75961) 2021-06-21 01:20:50
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The T52 Sturgeon Challenge — Part 10

[lasry-23] - 5 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from six "in-depth" ciphertexts built with T52ca. You are also provided with cribs for each message.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:32
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 1485 (282608) 2019-08-20 03:56:48
Michael Möller (michaelm) 1198 (253196) 2020-01-23 21:42:35
Snake (snk) 1181 (187783) 2020-03-23 16:25:18
Nicolas (nicosPavlov) 1159 (257791) 2020-07-24 11:17:51
#5 S Combes (jerva) 1143 (242717) 2020-12-30 16:22:54
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The T52 Sturgeon Challenge — Part 9

[lasry-22] - 5 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from six "in-depth" ciphertexts built with T52a/b. You are also provided with cribs for each message.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:31
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 1456 (282608) 2019-08-21 22:34:20
Michael Möller (michaelm) 1209 (253196) 2019-12-27 10:38:15
Snake (snk) 1181 (187783) 2020-03-20 17:08:26
Nicolas (nicosPavlov) 1160 (257791) 2020-07-23 10:42:30
#5 S Combes (jerva) 1142 (242717) 2021-01-10 15:04:47
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The T52 Sturgeon Challenge — Part 8

[lasry-21] - 7 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from six "in-depth" ciphertexts built with T52c. The key is partially known. You are also provided with cribs for each message.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:31
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#7) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 1660 (363488) 2019-08-14 06:40:22
Kurt Gebauer (Yokozuna) 1523 (282608) 2019-08-18 16:55:50
Michael Möller (michaelm) 1198 (253196) 2020-01-22 21:11:55
Snake (snk) 1181 (187783) 2020-03-22 13:03:26
#5 Nicolas (nicosPavlov) 1160 (257791) 2020-07-22 12:05:00
#6 S Combes (jerva) 1143 (242717) 2020-12-30 08:06:00
#7 Mike (RogueRamblers) 1132 (75961) 2021-06-21 01:44:40
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The T52 Sturgeon Challenge — Part 7

[lasry-20] - 5 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from ten "in-depth" ciphertexts built with T52ca. The key is partially known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:30
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 1725 (363488) 2019-08-13 16:29:12
Kurt Gebauer (Yokozuna) 1613 (282608) 2019-08-15 03:30:25
Snake (snk) 1181 (187783) 2020-03-23 09:59:53
Nicolas (nicosPavlov) 1158 (257791) 2020-08-02 04:21:22
#5 Michael Möller (michaelm) 1157 (253196) 2020-08-07 20:58:39
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The T52 Sturgeon Challenge — Part 6

[lasry-19] - 4 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from ten "in-depth" ciphertexts built with T52c. The key is partially known.
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Click here to get to the corresponding forum topic to share your opinion.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:30
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#4) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 1725 (363488) 2019-08-13 00:21:56
Kurt Gebauer (Yokozuna) 1613 (282608) 2019-08-15 14:53:37
Snake (snk) 1181 (187783) 2020-03-22 22:48:36
Nicolas (nicosPavlov) 1158 (257791) 2020-08-01 16:24:05
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The T52 Sturgeon Challenge — Part 5

[lasry-18] - 4 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext from ten "in-depth" ciphertexts built with T52ab. The key is partially known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-08-10 17:30
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#4) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 1824 (363488) 2019-08-12 16:35:58
Kurt Gebauer (Yokozuna) 1660 (282608) 2019-08-13 23:24:00
Snake (snk) 1181 (187783) 2020-03-20 17:07:07
Nicolas (nicosPavlov) 1158 (257791) 2020-08-05 14:47:04
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The T52 Sturgeon Challenge — Part 4

[lasry-17] - 9 users already solved this challenge, 1 is working on it.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext only from a T52ab ciphertext. The key is partially known.
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Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-07-22 23:20
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#9) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 1725 (282608) 2019-07-25 18:49:21
D3d4lu5 (D3d4lu5) 1385 (363488) 2019-08-11 20:05:00
Alain Collignon (vexilla72) 1256 (123666) 2019-10-01 18:59:20
Luigi Tomelli (archstanton) 1203 (127538) 2019-12-22 13:48:06
#5 Michael Möller (michaelm) 1201 (253196) 2019-12-28 11:47:25
#6 Snake (snk) 1177 (187783) 2020-03-19 22:22:52
#7 Dominik M. (Sgt. Pepper) 1176 (128575) 2020-03-27 15:39:42
#8 Nicolas (nicosPavlov) 1157 (257791) 2020-07-21 11:44:51
#9 S Combes (jerva) 1152 (242717) 2020-09-08 17:05:30
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The T52 Sturgeon Challenge — Part 3

[lasry-16] - 11 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext only from a T52d ciphertext. The key is partially known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-07-22 23:17
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#11) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2019-07-23 07:38:03
D3d4lu5 (D3d4lu5) 1824 (363488) 2019-07-24 06:19:13
Alain Collignon (vexilla72) 1256 (123666) 2019-10-01 14:41:57
Random Dude (rnd) 1238 (103645) 2019-10-21 21:48:09
#5 Luigi Tomelli (archstanton) 1204 (127538) 2019-12-19 13:52:50
#6 H. Lautenschlager (helmi) 1203 (56470) 2019-12-22 20:03:03
#7 Michael Möller (michaelm) 1180 (253196) 2020-03-08 15:55:33
#8 Snake (snk) 1178 (187783) 2020-03-18 22:24:04
#9 Nicolas (nicosPavlov) 1158 (257791) 2020-07-19 04:58:23
#10 S Combes (jerva) 1151 (242717) 2020-09-13 20:41:17
#11 Mike (RogueRamblers) 1131 (75961) 2021-06-17 01:02:56
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The T52 Sturgeon Challenge — Part 2

[lasry-15] - 14 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext only from a T52c ciphertext. The key is partially known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-07-22 23:15
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#14) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2019-07-23 00:55:17
D3d4lu5 (D3d4lu5) 1824 (363488) 2019-07-24 06:18:14
Alain Collignon (vexilla72) 1256 (123666) 2019-10-01 11:47:41
Random Dude (rnd) 1238 (103645) 2019-10-20 20:34:27
#5 H. Lautenschlager (helmi) 1212 (56470) 2019-12-01 22:01:22
#6 Luigi Tomelli (archstanton) 1208 (127538) 2019-12-11 18:04:06
#7 Michael Möller (michaelm) 1193 (253196) 2020-01-19 18:06:17
#8 Snake (snk) 1178 (187783) 2020-03-18 22:23:05
#9 Dominik M. (Sgt. Pepper) 1175 (128575) 2020-03-30 23:52:11
#10 Nobody (nobody) 1164 (42945) 2020-06-04 12:23:23
#11 Nicolas (nicosPavlov) 1158 (257791) 2020-07-15 14:49:31
#12 S Combes (jerva) 1152 (242717) 2020-09-10 07:36:41
#13 Mike (RogueRamblers) 1131 (75961) 2021-06-16 00:47:43
#14 George (Theofanidis) 1131 (123216) 2021-06-20 14:04:45
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The T52 Sturgeon Challenge — Part 1

[lasry-14] - 15 users already solved this challenge.
 
 
 

The Siemens and Halske T52 was a family of German teleprinter encryption devices used during WW2. This challenge is part of a series of challenges with T52. In this challenge, you need to recover the plaintext only from a T52ab ciphertext. The key is partially known.
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-07-13 23:11
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#15) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 1725 (282608) 2019-07-16 04:47:40
D3d4lu5 (D3d4lu5) 1725 (363488) 2019-07-16 17:31:02
Bart den Hartog (Bart13) 1444 (148936) 2019-07-26 16:40:28
Alain Collignon (vexilla72) 1247 (123666) 2019-10-01 11:45:38
#5 Random Dude (rnd) 1232 (103645) 2019-10-19 17:45:53
#6 H. Lautenschlager (helmi) 1211 (56470) 2019-11-25 18:14:29
#7 Luigi Tomelli (archstanton) 1204 (127538) 2019-12-10 14:42:26
#8 Michael Möller (michaelm) 1202 (253196) 2019-12-17 21:35:46
#9 Snake (snk) 1176 (187783) 2020-03-18 20:53:02
#10 Dominik M. (Sgt. Pepper) 1174 (128575) 2020-03-27 14:26:11
#11 Nobody (nobody) 1163 (42945) 2020-06-02 22:56:49
#12 Nicolas (nicosPavlov) 1157 (257791) 2020-07-15 13:20:13
#13 S Combes (jerva) 1151 (242717) 2020-09-08 17:03:27
#14 Mike (RogueRamblers) 1131 (75961) 2021-06-08 19:03:01
#15 George (Theofanidis) 1130 (123216) 2021-06-15 23:06:13
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Handycipher — Part 10

[kallick-25] - 1 user already solved this challenge.
 
 
 

Handycipher is a low-tech stream cipher, simple enough to permit pen-and-paper encrypting and decrypting of messages, while providing a significantly high level of security. Handycipher was first published in 2014 and further improved in 2015 and 2016. Part 10 of the Handycipher series presents the same challenge as Part 9 but with a different key choice. It is a ciphertext-only challenge.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-06-25 17:10
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#1) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 2000 (363488) 2019-06-26 12:28:07
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Handycipher made in love — Part 2

[kallick-24] - 17 users already solved this challenge, 1 is working on it.
 
 
 

Part 2 of the series "Handycipher made in love" is almost identical to Part 1 except that the solution you are asked for is the correct key that Alice used to produce the ciphertext rather than the short message embedded in the plaintext.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-05-21 16:47
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#17) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 2000 (206965) 2019-05-21 19:53:02
D3d4lu5 (D3d4lu5) 2000 (363488) 2019-05-21 22:37:28
Viktor (Veselovský) 2000 (169444) 2019-05-21 23:37:36
Kurt Gebauer (Yokozuna) 2000 (282608) 2019-05-22 04:17:23
#5 Alain Collignon (vexilla72) 2000 (123666) 2019-05-22 11:15:40
#6 Michael Möller (michaelm) 2000 (253196) 2019-05-22 12:28:56
#7 Danny Higgins (hamster147) 2000 (39638) 2019-05-22 12:46:19
#8 Dominik M. (Sgt. Pepper) 2000 (128575) 2019-05-22 15:03:47
#9 Eugene (lim0n) 1824 (178540) 2019-05-23 13:37:11
#10 George (Theofanidis) 1725 (123216) 2019-05-23 23:00:36
#11 Random Dude (rnd) 1469 (103645) 2019-05-31 23:52:30
#12 E.T (Ertheb) 1324 (81809) 2019-06-23 17:55:08
#13 Bart den Hartog (Bart13) 1244 (148936) 2019-08-11 23:04:07
#14 Silvia Kortmann (mikinsget) 1152 (20341) 2020-07-04 16:11:25
#15 Nicolas (nicosPavlov) 1147 (257791) 2020-08-26 07:12:20
#16 Em Doulgerakis (Greko) 1136 (193799) 2021-01-22 18:34:44
#17 madness (madness) 1128 (71592) 2021-06-17 18:13:56
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Homophonic Encryption — Part 4

[kopal-04] - 28 users already solved this challenge.
 
 
 

Homophonic encryption is a modified version of the monoalphabetic substitution: One plaintext symbol can be substituted by more than one ciphertext symbol. In part 4 of this series we consider a distribution of the homophones based on English language statistics like in part 2, but the alphabet doesn't contain the blank. This is a ciphertext-only challenge. Try to crack the ciphertext and extract a specific word from the plaintext.
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Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-05-08 21:31
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#28) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 2000 (169444) 2019-05-09 00:56:19
Snake (snk) 2000 (187783) 2019-05-09 14:10:58
Armin Krauss (argh) 2000 (206965) 2019-05-09 17:58:49
George Lasry (george4096) 2000 (399565) 2019-05-09 20:48:39
#5 D3d4lu5 (D3d4lu5) 1824 (363488) 2019-05-10 18:25:33
#6 E.T (Ertheb) 1613 (81809) 2019-05-13 19:52:53
#7 Random Dude (rnd) 1456 (103645) 2019-05-20 13:42:29
#8 Dominik M. (Sgt. Pepper) 1444 (128575) 2019-05-21 18:51:04
#9 sarah b (silva) 1321 (47847) 2019-06-12 14:03:49
#10 Stephan (Stephje1978) 1254 (27064) 2019-07-20 19:51:56
#11 Bart den Hartog (Bart13) 1251 (148936) 2019-07-23 02:41:07
#12 Gerd Wilts (gerdw) 1246 (50534) 2019-07-27 22:50:35
#13 Danny Higgins (hamster147) 1207 (39638) 2019-09-28 23:53:20
#14 Em Doulgerakis (Greko) 1198 (193799) 2019-10-21 19:24:28
#15 George (Theofanidis) 1196 (123216) 2019-10-27 20:00:15
#16 Alain Collignon (vexilla72) 1180 (123666) 2019-12-22 12:16:59
#17 madness (madness) 1170 (71592) 2020-02-10 11:37:44
#18 Thomas (Thomas4897) 1167 (36141) 2020-02-28 18:57:12
#19 J-L Morel (Rossignol) 1162 (42130) 2020-03-31 18:24:56
#20 Eugene (lim0n) 1161 (178540) 2020-04-07 14:18:21
#21 Derek Hatton (alfred_noble) 1140 (33998) 2020-11-02 21:47:30
#22 Michael (FoM) 1138 (57794) 2020-12-04 17:55:52
#23 Mike (RogueRamblers) 1134 (75961) 2021-02-08 17:02:56
#24 Lane Williams (planetlane) 1131 (34637) 2021-04-01 21:35:05
#25 gordon (sir5) 1129 (16181) 2021-05-12 12:00:48
#26 Martin (martinbucher) 1129 (38365) 2021-05-13 16:47:53
#27 Luigi Tomelli (archstanton) 1129 (127538) 2021-05-16 17:49:42
#28 Eric (ExAstris) 1129 (54941) 2021-05-19 03:49:58
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Homophonic Encryption — Part 3

[kopal-03] - 29 users already solved this challenge, 1 is working on it.
 
 
 

Homophonic encryption is a modified version of the monoalphabetic substitution: One plaintext symbol can be substituted by more than one ciphertext symbol. In part 3 of this series every plaintext symbol has the same number of possible substitutions like in part 1, but the alphabet doesn't contain the blank. This is a ciphertext-only challenge. Try to crack the ciphertext and extract a specific word from the plaintext.
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Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-05-08 21:30
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#29) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 2000 (169444) 2019-05-09 00:41:40
Alain Collignon (vexilla72) 2000 (123666) 2019-05-09 10:44:10
Dominik M. (Sgt. Pepper) 2000 (128575) 2019-05-09 13:01:44
Snake (snk) 2000 (187783) 2019-05-09 13:48:05
#5 D3d4lu5 (D3d4lu5) 2000 (363488) 2019-05-09 17:16:18
#6 Armin Krauss (argh) 2000 (206965) 2019-05-09 17:34:33
#7 George Lasry (george4096) 2000 (399565) 2019-05-09 20:51:40
#8 Kurt Gebauer (Yokozuna) 1660 (282608) 2019-05-12 09:56:05
#9 E.T (Ertheb) 1613 (81809) 2019-05-13 19:39:06
#10 Random Dude (rnd) 1469 (103645) 2019-05-19 06:21:43
#11 Eugene (lim0n) 1469 (178540) 2019-05-19 07:57:08
#12 sarah b (silva) 1444 (47847) 2019-05-21 10:23:59
#13 Danny Higgins (hamster147) 1312 (39638) 2019-06-15 09:29:43
#14 George (Theofanidis) 1310 (123216) 2019-06-15 23:35:10
#15 Stephan (Stephje1978) 1254 (27064) 2019-07-20 19:44:17
#16 Bart den Hartog (Bart13) 1251 (148936) 2019-07-23 01:31:01
#17 Gerd Wilts (gerdw) 1246 (50534) 2019-07-27 22:34:51
#18 Em Doulgerakis (Greko) 1198 (193799) 2019-10-20 22:10:48
#19 madness (madness) 1170 (71592) 2020-02-10 10:31:39
#20 Thomas (Thomas4897) 1167 (36141) 2020-02-29 08:11:06
#21 J-L Morel (Rossignol) 1162 (42130) 2020-03-31 17:34:46
#22 Derek Hatton (alfred_noble) 1140 (33998) 2020-11-02 19:28:52
#23 Michael (FoM) 1138 (57794) 2020-12-04 17:34:08
#24 Mike (RogueRamblers) 1134 (75961) 2021-01-31 01:22:41
#25 Lane Williams (planetlane) 1131 (34637) 2021-04-01 20:55:27
#26 gordon (sir5) 1129 (16181) 2021-05-12 11:50:10
#27 Martin (martinbucher) 1129 (38365) 2021-05-13 16:36:41
#28 Luigi Tomelli (archstanton) 1129 (127538) 2021-05-14 18:17:35
#29 Eric (ExAstris) 1129 (54941) 2021-05-19 02:13:17
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Homophonic Encryption — Part 2

[kopal-02] - 30 users already solved this challenge, 1 is working on it.
 
 
 

Homophonic encryption is a modified version of the monoalphabetic substitution: One plaintext symbol can be substituted by more than one ciphertext symbol. In part 2 of this series we consider a distribution of the homophones based on English language statistics. This is a ciphertext-only challenge. Try to crack the ciphertext and extract a specific word from the plaintext.
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Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-05-08 21:30
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#30) Achieved points (Global score) y-m-d - h:m:s

George Lasry (george4096) 1725 (399565) 2019-05-10 22:02:30
Armin Krauss (argh) 1725 (206965) 2019-05-10 22:04:09
Snake (snk) 1725 (187783) 2019-05-10 22:29:03
Alain Collignon (vexilla72) 1725 (123666) 2019-05-10 23:47:11
#5 Viktor (Veselovský) 1725 (169444) 2019-05-11 00:58:36
#6 H. Lautenschlager (helmi) 1725 (56470) 2019-05-11 19:53:59
#7 Kurt Gebauer (Yokozuna) 1725 (282608) 2019-05-11 20:56:51
#8 E.T (Ertheb) 1613 (81809) 2019-05-13 19:28:56
#9 D3d4lu5 (D3d4lu5) 1576 (363488) 2019-05-14 06:05:32
#10 Eugene (lim0n) 1523 (178540) 2019-05-16 13:32:40
#11 sarah b (silva) 1485 (47847) 2019-05-18 19:57:39
#12 Random Dude (rnd) 1469 (103645) 2019-05-19 05:44:02
#13 George (Theofanidis) 1469 (123216) 2019-05-19 16:12:16
#14 Dominik M. (Sgt. Pepper) 1433 (128575) 2019-05-22 15:21:28
#15 Danny Higgins (hamster147) 1423 (39638) 2019-05-22 21:56:59
#16 Stephan (Stephje1978) 1254 (27064) 2019-07-20 18:47:10
#17 Bart den Hartog (Bart13) 1251 (148936) 2019-07-23 00:42:48
#18 Gerd Wilts (gerdw) 1246 (50534) 2019-07-27 23:58:09
#19 Em Doulgerakis (Greko) 1197 (193799) 2019-10-22 22:15:01
#20 madness (madness) 1170 (71592) 2020-02-10 21:13:23
#21 Thomas (Thomas4897) 1167 (36141) 2020-02-28 18:19:21
#22 J-L Morel (Rossignol) 1162 (42130) 2020-03-30 19:13:06
#23 Derek Hatton (alfred_noble) 1140 (33998) 2020-11-02 23:44:54
#24 Michael (FoM) 1138 (57794) 2020-12-04 02:17:07
#25 Mike (RogueRamblers) 1134 (75961) 2021-01-31 01:44:55
#26 Lane Williams (planetlane) 1131 (34637) 2021-04-01 16:42:11
#27 gordon (sir5) 1129 (16181) 2021-05-12 11:34:13
#28 Martin (martinbucher) 1129 (38365) 2021-05-13 15:22:49
#29 Luigi Tomelli (archstanton) 1129 (127538) 2021-05-13 20:11:20
#30 Eric (ExAstris) 1129 (54941) 2021-05-19 02:48:11
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Homophonic Encryption — Part 1

[kopal-01] - 35 users already solved this challenge.
 
 
 

Homophonic encryption is a modified version of the monoalphabetic substitution: One plaintext symbol can be substituted by more than one ciphertext symbol. In part 1 of this series every plaintext symbol has the same number of possible substitutions. This is a ciphertext-only challenge. Try to crack the ciphertext and extract a specific word from the plaintext.
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-05-04 15:22
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#35) Achieved points (Global score) y-m-d - h:m:s

Snake (snk) 2000 (187783) 2019-05-04 20:15:46
Armin Krauss (argh) 2000 (206965) 2019-05-04 23:35:06
D3d4lu5 (D3d4lu5) 2000 (363488) 2019-05-05 04:23:38
Kurt Gebauer (Yokozuna) 2000 (282608) 2019-05-05 13:33:42
#5 H. Lautenschlager (helmi) 2000 (56470) 2019-05-05 13:50:31
#6 Dominik M. (Sgt. Pepper) 2000 (128575) 2019-05-05 15:17:09
#7 George (Theofanidis) 1824 (123216) 2019-05-05 19:47:28
#8 Marc (rcll0891) 1824 (24004) 2019-05-05 22:43:25
#9 Alain Collignon (vexilla72) 1824 (123666) 2019-05-06 11:43:14
#10 E.T (Ertheb) 1824 (81809) 2019-05-06 14:05:14
#11 Viktor (Veselovský) 1725 (169444) 2019-05-06 19:00:08
#12 Michael Möller (michaelm) 1725 (253196) 2019-05-06 22:40:30
#13 George Lasry (george4096) 1660 (399565) 2019-05-07 22:40:03
#14 sarah b (silva) 1523 (47847) 2019-05-12 10:44:07
#15 Eugene (lim0n) 1469 (178540) 2019-05-15 14:53:33
#16 Random Dude (rnd) 1444 (103645) 2019-05-17 03:56:02
#17 Danny Higgins (hamster147) 1391 (39638) 2019-05-22 17:04:47
#18 Hans Joachim Girulat (joregi) 1261 (36278) 2019-07-09 15:30:08
#19 Stephan (Stephje1978) 1249 (27064) 2019-07-20 19:47:49
#20 Bart den Hartog (Bart13) 1247 (148936) 2019-07-22 23:32:57
#21 Gerd Wilts (gerdw) 1243 (50534) 2019-07-27 20:56:08
#22 Em Doulgerakis (Greko) 1197 (193799) 2019-10-21 10:10:45
#23 Jasmin (Miles) 1176 (8987) 2020-01-08 01:58:05
#24 madness (madness) 1170 (71592) 2020-02-10 10:30:43
#25 Thomas (Thomas4897) 1166 (36141) 2020-02-28 18:14:54
#26 J-L Morel (Rossignol) 1162 (42130) 2020-03-29 17:10:19
#27 Martin (martinbucher) 1156 (38365) 2020-05-17 12:33:58
#28 Nicolas (nicosPavlov) 1146 (257791) 2020-08-23 05:43:56
#29 Derek Hatton (alfred_noble) 1140 (33998) 2020-11-02 23:57:15
#30 Lane Williams (planetlane) 1140 (34637) 2020-11-03 18:58:58
#31 Michael (FoM) 1138 (57794) 2020-12-02 20:22:33
#32 Mike (RogueRamblers) 1134 (75961) 2021-01-30 19:02:17
#33 Luigi Tomelli (archstanton) 1129 (127538) 2021-05-11 17:51:28
#34 gordon (sir5) 1129 (16181) 2021-05-12 11:30:59
#35 Eric (ExAstris) 1128 (54941) 2021-05-19 02:37:40
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Handycipher made in love — Part 1

[theofanidis-09] - 22 users already solved this challenge.
 
 
 

Strange things happen when you're in love. This challenge is about how the plaintext can be revealed when Handycipher is used in a wrong way.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-02-16 12:29
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#22) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 2000 (206965) 2019-02-16 14:52:29
D3d4lu5 (D3d4lu5) 2000 (363488) 2019-02-16 16:30:13
Michael Möller (michaelm) 2000 (253196) 2019-02-16 18:53:09
George Lasry (george4096) 2000 (399565) 2019-02-16 21:36:16
#5 Alain Collignon (vexilla72) 2000 (123666) 2019-02-16 22:05:39
#6 Viktor (Veselovský) 2000 (169444) 2019-02-16 23:50:47
#7 Kurt Gebauer (Yokozuna) 2000 (282608) 2019-02-17 05:12:50
#8 Dominik M. (Sgt. Pepper) 1824 (128575) 2019-02-17 16:28:10
#9 Snake (snk) 1824 (187783) 2019-02-17 19:03:26
#10 Rainer Zufall (kiekuk) 1406 (56786) 2019-03-04 14:32:25
#11 sarah b (silva) 1281 (47847) 2019-04-10 10:11:09
#12 curmudgeon (curmudgeon) 1262 (1973) 2019-04-23 06:26:13
#13 Beamofoldlight (Beamofoldlight) 1250 (3745) 2019-05-03 16:05:30
#14 Danny Higgins (hamster147) 1236 (39638) 2019-05-19 22:53:22
#15 Eugene (lim0n) 1233 (178540) 2019-05-23 14:09:42
#16 Random Dude (rnd) 1227 (103645) 2019-05-31 13:45:56
#17 E.T (Ertheb) 1216 (81809) 2019-06-19 17:29:41
#18 Bart den Hartog (Bart13) 1199 (148936) 2019-07-29 05:55:03
#19 Silvia Kortmann (mikinsget) 1144 (20341) 2020-07-03 12:30:53
#20 Nicolas (nicosPavlov) 1139 (257791) 2020-08-25 18:38:22
#21 Em Doulgerakis (Greko) 1130 (193799) 2021-01-22 17:19:59
#22 madness (madness) 1124 (71592) 2021-06-17 04:01:37
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Monoalphabetic Substitution with Nostradamus Flavor

[theofanidis-08] - 28 users already solved this challenge, 3 are working on it.
 
 
 

What would Nostradamus do to make a mono-alphabetic substitution harder to break?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2019-02-16 12:28
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#28) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 2000 (206965) 2019-02-16 13:26:09
D3d4lu5 (D3d4lu5) 2000 (363488) 2019-02-16 15:57:07
Dominik M. (Sgt. Pepper) 2000 (128575) 2019-02-16 19:22:15
George Lasry (george4096) 2000 (399565) 2019-02-16 21:43:46
#5 Viktor (Veselovský) 2000 (169444) 2019-02-16 23:02:15
#6 Alain Collignon (vexilla72) 2000 (123666) 2019-02-16 23:07:32
#7 Kurt Gebauer (Yokozuna) 2000 (282608) 2019-02-17 06:54:14
#8 Snake (snk) 1824 (187783) 2019-02-17 17:11:33
#9 Luigi Tomelli (archstanton) 1660 (127538) 2019-02-19 13:04:04
#10 Lane Williams (planetlane) 1660 (34637) 2019-02-19 16:02:06
#11 Random Dude (rnd) 1660 (103645) 2019-02-19 17:26:52
#12 Karl Schutt (günter) 1660 (44374) 2019-02-19 18:42:32
#13 sarah b (silva) 1613 (47847) 2019-02-20 15:14:33
#14 Pierre Robier (tripleedged) 1613 (5916) 2019-02-20 21:29:51
#15 Rainer Zufall (kiekuk) 1444 (56786) 2019-02-28 16:30:24
#16 E.T (Ertheb) 1261 (81809) 2019-04-23 17:55:37
#17 Hans Joachim Girulat (joregi) 1223 (36278) 2019-06-07 22:57:11
#18 Michael (FoM) 1217 (57794) 2019-06-18 17:17:19
#19 Bart den Hartog (Bart13) 1185 (148936) 2019-09-11 18:27:40
#20 Derek Hatton (alfred_noble) 1160 (33998) 2020-01-29 23:02:28
#21 Thomas (Thomas4897) 1156 (36141) 2020-03-01 18:09:54
#22 Eugene (lim0n) 1155 (178540) 2020-03-06 13:47:39
#23 Mike (RogueRamblers) 1147 (75961) 2020-05-18 02:13:45
#24 Somebody (Achidutzu) 1146 (14883) 2020-06-07 20:54:40
#25 Nicolas (nicosPavlov) 1140 (257791) 2020-08-23 12:05:05
#26 Em Doulgerakis (Greko) 1132 (193799) 2020-12-28 17:35:53
#27 J-L Morel (Rossignol) 1131 (42130) 2021-01-15 16:45:37
#28 Eric (ExAstris) 1126 (54941) 2021-04-21 22:27:39
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"The Road" — Part 3

[gutgesell-08] - 0 users already solved this challenge, 2 are working on it.
 
 
 

Once upon a time, there was a three-part challenge which was inspired by Kryptos and is based on a fairy tale. Can you solve this mysterious challenge?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-12-08 17:45
Maximum number of attempts for this challenge: 15

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"The Road" — Part 2

[gutgesell-07] - 0 users already solved this challenge.
 
 
 

Once upon a time, there was a three-part challenge which was inspired by Kryptos and is based on a fairy tale. Can you solve this mysterious challenge?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-12-08 17:42
Maximum number of attempts for this challenge: 15

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No one solved the challenge right now. Be the first!
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"The Road" — Part 1

[gutgesell-06] - 5 users already solved this challenge.
 
 
 

Once upon a time, there was a three-part challenge which was inspired by Kryptos and is based on a fairy tale. Can you solve this mysterious challenge?
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-12-08 17:27
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 1824 (206965) 2018-12-10 15:47:26
Viktor (Veselovský) 1613 (169444) 2018-12-13 15:15:16
D3d4lu5 (D3d4lu5) 1315 (363488) 2019-01-14 08:37:31
Eugene (lim0n) 1163 (178540) 2019-10-30 12:18:39
#5 Snake (snk) 1160 (187783) 2019-11-14 21:04:35
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Breaking a Filter Generator

[cli-03] - 19 users already solved this challenge.
 
 
 

You are given a part of a keystream, which was produced by a filter generator. Can you find the missing keystream bytes?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-09-25 14:22
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#19) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 1824 (282608) 2018-09-26 21:06:06
Viktor (Veselovský) 1725 (169444) 2018-09-27 22:20:26
roehm (roehm) 1725 (5399) 2018-09-28 00:56:29
D3d4lu5 (D3d4lu5) 1725 (363488) 2018-09-28 02:01:18
#5 Alain Collignon (vexilla72) 1660 (123666) 2018-09-28 16:19:20
#6 S Combes (jerva) 1660 (242717) 2018-09-29 13:49:15
#7 Nicolas (nicosPavlov) 1469 (257791) 2018-10-06 07:29:57
#8 E.T (Ertheb) 1385 (81809) 2018-10-15 13:04:25
#9 George Lasry (george4096) 1330 (399565) 2018-10-27 02:15:58
#10 Random Dude (rnd) 1318 (103645) 2018-10-30 18:04:00
#11 Kasia (kasia-tutej) 1232 (53366) 2018-12-31 19:29:06
#12 ykaridi (ykaridi) 1192 (7035) 2019-03-27 20:24:51
#13 Bart den Hartog (Bart13) 1164 (148936) 2019-08-06 16:56:35
#14 Eugene (lim0n) 1161 (178540) 2019-08-30 12:17:05
#15 Snake (snk) 1156 (187783) 2019-10-05 09:29:41
#16 Noam Gutterman (Noam528) 1150 (1150) 2019-12-02 11:44:58
#17 madness (madness) 1138 (71592) 2020-04-27 13:55:25
#18 Em Doulgerakis (Greko) 1122 (193799) 2021-03-07 14:14:24
#19 Luigi Tomelli (archstanton) 1119 (127538) 2021-06-04 19:29:37
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Trendy Messenger

[minihold-03] - 31 users already solved this challenge, 2 are working on it.
 
 
 

Sniffing on the WiFi, you notice an ElGamal encrypted message. Are you able to compute it?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-06-12 13:26
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#31) Achieved points (Global score) y-m-d - h:m:s

D3d4lu5 (D3d4lu5) 2000 (363488) 2018-06-13 01:04:34
Kurt Gebauer (Yokozuna) 2000 (282608) 2018-06-13 11:25:42
Dominik M. (Sgt. Pepper) 1824 (128575) 2018-06-13 14:33:57
Viktor (Veselovský) 1725 (169444) 2018-06-14 19:05:40
#5 Alain Collignon (vexilla72) 1547 (123666) 2018-06-19 07:44:33
#6 George (Theofanidis) 1523 (123216) 2018-06-19 19:26:48
#7 Vlad (Vlad94) 1523 (1523) 2018-06-19 20:50:56
#8 Teodoru catalin Andrei (teodoru) 1502 (5698) 2018-06-20 16:01:04
#9 Eric (ExAstris) 1469 (54941) 2018-06-22 16:47:20
#10 E.T (Ertheb) 1456 (81809) 2018-06-23 14:51:57
#11 Christophe BORELLY (cb34) 1433 (12358) 2018-06-25 13:53:33
#12 Silvia Kortmann (mikinsget) 1406 (20341) 2018-06-29 10:26:04
#13 Armin Krauss (argh) 1398 (206965) 2018-06-29 14:25:48
#14 Nicolas (nicosPavlov) 1330 (257791) 2018-07-13 16:23:13
#15 Mihail (plexor) 1327 (16827) 2018-07-14 19:56:05
#16 Alain (Integral) 1307 (207924) 2018-07-21 13:53:14
#17 Em Doulgerakis (Greko) 1288 (193799) 2018-07-30 16:34:08
#18 Karl Schutt (günter) 1278 (44374) 2018-08-06 05:43:46
#19 Javantea (Javantea) 1218 (40816) 2018-10-10 03:19:11
#20 Random Dude (rnd) 1212 (103645) 2018-10-22 22:43:50
#21 kilink (kilink) 1200 (8053) 2018-11-19 00:27:26
#22 Snake (snk) 1199 (187783) 2018-11-23 16:13:11
#23 Rainer Zufall (kiekuk) 1199 (56786) 2018-11-23 21:37:49
#24 Luigi Tomelli (archstanton) 1191 (127538) 2018-12-15 19:54:53
#25 Kasia (kasia-tutej) 1187 (53366) 2018-12-31 17:02:03
#26 Will (nitrow) 1164 (6807) 2019-04-26 11:30:50
#27 Eugene (lim0n) 1161 (178540) 2019-05-13 11:02:50
#28 Bart den Hartog (Bart13) 1153 (148936) 2019-07-22 17:30:41
#29 Bernd (tryone144) 1131 (8066) 2020-04-26 16:38:14
#30 madness (madness) 1131 (71592) 2020-04-27 16:40:02
#31 Marco Cinelli (Snap) 1129 (37769) 2020-06-05 09:37:44
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Fastest in the West

[minihold-01] - 30 users already solved this challenge.
 
 
 

Buying a train ticket via credit card should not be a problem — actually. Can you solve the subset-sum problem to get your train?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-06-12 13:24
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#30) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2018-06-13 03:24:07
D3d4lu5 (D3d4lu5) 2000 (363488) 2018-06-13 07:45:23
Alain Collignon (vexilla72) 2000 (123666) 2018-06-13 10:36:19
Dominik M. (Sgt. Pepper) 1824 (128575) 2018-06-14 13:22:36
#5 Viktor (Veselovský) 1725 (169444) 2018-06-14 16:21:58
#6 George (Theofanidis) 1660 (123216) 2018-06-15 20:11:16
#7 E.T (Ertheb) 1576 (81809) 2018-06-17 22:53:05
#8 Diaconu Bogdan (bogdan_walle) 1523 (1723) 2018-06-19 16:36:32
#9 Teodoru catalin Andrei (teodoru) 1502 (5698) 2018-06-20 15:58:58
#10 Eric (ExAstris) 1485 (54941) 2018-06-21 18:56:13
#11 Alain (Integral) 1485 (207924) 2018-06-22 00:15:18
#12 Snake (snk) 1469 (187783) 2018-06-22 22:48:21
#13 Armin Krauss (argh) 1398 (206965) 2018-06-29 15:27:43
#14 Nicolas (nicosPavlov) 1391 (257791) 2018-07-01 04:20:26
#15 Christophe BORELLY (cb34) 1385 (12358) 2018-07-02 11:31:03
#16 George Lasry (george4096) 1367 (399565) 2018-07-04 23:19:04
#17 Em Doulgerakis (Greko) 1288 (193799) 2018-07-30 15:10:17
#18 Michael Möller (michaelm) 1233 (253196) 2018-09-16 15:06:39
#19 Random Dude (rnd) 1212 (103645) 2018-10-21 20:56:52
#20 Rainer Zufall (kiekuk) 1206 (56786) 2018-11-03 21:05:24
#21 kilink (kilink) 1200 (8053) 2018-11-19 00:02:07
#22 Luigi Tomelli (archstanton) 1191 (127538) 2018-12-16 10:43:50
#23 Kasia (kasia-tutej) 1187 (53366) 2018-12-31 16:12:51
#24 Bart den Hartog (Bart13) 1153 (148936) 2019-07-22 21:37:01
#25 Eugene (lim0n) 1152 (178540) 2019-08-01 14:43:32
#26 Dr. Peter Uelkes (RandyWaterhouse) 1150 (9990) 2019-08-18 12:10:20
#27 Karl Schutt (günter) 1139 (44374) 2020-01-01 12:07:46
#28 madness (madness) 1135 (71592) 2020-02-28 17:56:18
#29 Marco Cinelli (Snap) 1129 (37769) 2020-06-06 16:02:43
#30 DS (DS8279) 1121 (29732) 2020-12-20 11:20:19
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Summer Job

[minihold-02] - 45 users already solved this challenge, 2 are working on it.
 
 
 

During your summer job in an Austrian weekly magazine a mysterious letter arrives. Are you able to decrypt the message?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-06-12 13:16
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#45) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2018-06-12 21:37:26
E.T (Ertheb) 2000 (81809) 2018-06-12 21:48:19
Viktor (Veselovský) 2000 (169444) 2018-06-12 23:34:15
D3d4lu5 (D3d4lu5) 2000 (363488) 2018-06-13 06:19:26
#5 Alain Collignon (vexilla72) 1824 (123666) 2018-06-13 15:53:42
#6 Dominik M. (Sgt. Pepper) 1725 (128575) 2018-06-14 22:17:14
#7 George (Theofanidis) 1613 (123216) 2018-06-17 11:54:19
#8 John Smith (Froyo10) 1547 (1747) 2018-06-18 20:24:50
#9 Teodoru catalin Andrei (teodoru) 1502 (5698) 2018-06-20 15:57:16
#10 Eric (ExAstris) 1485 (54941) 2018-06-22 04:38:27
#11 Alain (Integral) 1469 (207924) 2018-06-23 10:16:28
#12 Silvia Kortmann (mikinsget) 1433 (20341) 2018-06-26 01:36:50
#13 Armin Krauss (argh) 1406 (206965) 2018-06-28 20:33:36
#14 George Lasry (george4096) 1367 (399565) 2018-07-04 22:04:09
#15 Snake (snk) 1330 (187783) 2018-07-13 21:05:10
#16 Nicolas (nicosPavlov) 1327 (257791) 2018-07-15 05:49:19
#17 Mihail (plexor) 1324 (16827) 2018-07-16 09:04:57
#18 Em Doulgerakis (Greko) 1294 (193799) 2018-07-27 15:28:14
#19 Karl Schutt (günter) 1279 (44374) 2018-08-04 21:30:42
#20 Hans Joachim Girulat (joregi) 1278 (36278) 2018-08-05 17:41:25
#21 Andrei Gasparovici (fullofvim) 1261 (1861) 2018-08-18 07:52:36
#22 Random Dude (rnd) 1217 (103645) 2018-10-13 03:24:44
#23 Rainer Zufall (kiekuk) 1206 (56786) 2018-11-03 12:37:24
#24 Hans Peter (hanspeter) 1204 (52356) 2018-11-08 18:53:31
#25 kilink (kilink) 1200 (8053) 2018-11-18 22:14:22
#26 Luigi Tomelli (archstanton) 1191 (127538) 2018-12-17 12:59:10
#27 Kasia (kasia-tutej) 1187 (53366) 2018-12-31 17:36:11
#28 Szabó Zoltán (szabo.z87) 1185 (55604) 2019-01-08 08:51:43
#29 Nofre Tete (noffi) 1185 (26507) 2019-01-08 21:53:11
#30 zuben c3 (zuben-c3) 1184 (27154) 2019-01-11 10:59:35
#31 Eugene (lim0n) 1161 (178540) 2019-05-12 13:21:42
#32 Marco Cinelli (Snap) 1160 (37769) 2019-05-21 13:00:26
#33 Gerd Wilts (gerdw) 1153 (50534) 2019-07-14 17:26:39
#34 Bart den Hartog (Bart13) 1153 (148936) 2019-07-16 05:21:53
#35 Karl (Aureon) 1143 (2534) 2019-10-30 10:44:19
#36 Lane Williams (planetlane) 1139 (34637) 2019-12-25 21:18:35
#37 Andrei Palangean (palangeanad) 1136 (1136) 2020-02-10 11:55:24
#38 madness (madness) 1132 (71592) 2020-04-21 03:46:01
#39 Bernd (tryone144) 1126 (8066) 2020-08-09 20:09:41
#40 Polaris (Polaris) 1126 (32963) 2020-08-10 01:00:10
#41 Derek Hatton (alfred_noble) 1122 (33998) 2020-11-14 20:15:52
#42 Nicky (Wokini) 1122 (18494) 2020-11-17 13:57:34
#43 DS (DS8279) 1122 (29732) 2020-11-19 21:40:39
#44 Somebody (Achidutzu) 1117 (14883) 2021-04-25 21:14:06
#45 Claude Vaillancourt (Cl3v3r) 1116 (44129) 2021-05-23 19:22:30
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Weakened ElsieFour — Part 2

[rotthaler-08] - 0 users already solved this challenge, 2 are working on it.
 
 
 

The challenges for the weakened ElsieFour serve as an exercise and use an intentionally weakened version of LC4. ElsieFour combines ideas of modern RC4 stream cipher, historical Playfair cipher and plaintext-dependent keystreams. It can be computed manually. Part 2 is a partly-known key challenge which provides 12 consecutive characters of the key.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-04-28 16:36
Maximum number of attempts for this challenge: 15

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No one solved the challenge right now. Be the first!
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Weakened ElsieFour — Part 1

[rotthaler-07] - 4 users already solved this challenge.
 
 
 

The challenges for the weakened ElsieFour serve as an exercise and use an intentionally weakened version of LC4. ElsieFour combines ideas of modern RC4 stream cipher, historical Playfair cipher and plaintext-dependent keystreams. It can be computed manually. Part 1 is a partly-known key challenge which provides the first 12 characters of the key.
Read more...

Click here to get to the corresponding forum topic to share your opinion.
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Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-04-28 16:29
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#4) Achieved points (Global score) y-m-d - h:m:s

George (Theofanidis) 1200 (123216) 2018-10-06 20:53:41
Michael Möller (michaelm) 1176 (253196) 2019-01-02 09:55:59
D3d4lu5 (D3d4lu5) 1138 (363488) 2019-11-28 19:27:00
Eugene (lim0n) 1115 (178540) 2021-05-10 19:34:04
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The Einstein Enigma

[hiker-01] - 55 users already solved this challenge, 4 are working on it.
 
 
 

The hero of the book has to decode a manuscript — seven lines of it are here for you. These lines were encoded with a mixture of classic methods — anagrams, two position-dependent monoalphabetic substitutions and Atbash. Can you help him?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2018-02-07 23:40
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#55) Achieved points (Global score) y-m-d - h:m:s

H. Lautenschlager (helmi) 2000 (56470) 2018-02-08 18:35:02
Kurt Gebauer (Yokozuna) 2000 (282608) 2018-02-08 20:23:50
Snake (snk) 2000 (187783) 2018-02-08 21:10:28
Alain Collignon (vexilla72) 1824 (123666) 2018-02-09 07:29:58
#5 Mir Dim (mir0soft) 1824 (79760) 2018-02-09 09:40:24
#6 Dominik M. (Sgt. Pepper) 1824 (128575) 2018-02-09 12:33:10
#7 Mihail (plexor) 1725 (16827) 2018-02-10 13:44:32
#8 Lane Williams (planetlane) 1660 (34637) 2018-02-11 04:56:48
#9 E.T (Ertheb) 1660 (81809) 2018-02-11 17:34:28
#10 Armin Krauss (argh) 1613 (206965) 2018-02-12 00:55:11
#11 Nicolas (nicosPavlov) 1613 (257791) 2018-02-12 03:48:24
#12 chris_3stones (3stones) 1613 (38845) 2018-02-12 20:31:25
#13 George (Theofanidis) 1613 (123216) 2018-02-12 20:34:04
#14 Marc (rcll0891) 1576 (24004) 2018-02-12 23:54:59
#15 Sebastian Slupina (Grandwizard) 1547 (10866) 2018-02-14 23:36:16
#16 Viktor (Veselovský) 1523 (169444) 2018-02-15 18:12:30
#17 Manu (manu87) 1502 (2979) 2018-02-16 09:14:05
#18 Rainer Zufall (kiekuk) 1414 (56786) 2018-02-23 21:36:11
#19 j.h. (haegarq) 1373 (15352) 2018-03-01 08:45:39
#20 Jhoana Reichert (15faustino) 1324 (1724) 2018-03-13 01:16:54
#21 Nofre Tete (noffi) 1324 (26507) 2018-03-13 19:04:33
#22 Norbert Biermann (Norbert) 1305 (47790) 2018-03-20 11:27:40
#23 Ignacio (Moebiusar) 1302 (7390) 2018-03-21 13:59:00
#24 D3d4lu5 (D3d4lu5) 1278 (363488) 2018-04-03 12:25:30
#25 Szabó Zoltán (szabo.z87) 1264 (55604) 2018-04-13 13:36:52
#26 Allisat (psychohasii) 1248 (4356) 2018-04-28 00:36:38
#27 Anna (ronja11) 1236 (4244) 2018-05-11 14:24:08
#28 Eric (ExAstris) 1224 (54941) 2018-05-28 02:56:23
#29 Manfred Wurm (Tschabobo) 1216 (8935) 2018-06-11 09:22:40
#30 Alain (Integral) 1210 (207924) 2018-06-24 10:58:21
#31 Em Doulgerakis (Greko) 1197 (193799) 2018-07-27 14:56:52
#32 Hans Joachim Girulat (joregi) 1197 (36278) 2018-07-27 19:49:03
#33 Danny Higgins (hamster147) 1190 (39638) 2018-08-18 22:44:30
#34 Michael Möller (michaelm) 1186 (253196) 2018-09-02 09:58:19
#35 Random Dude (rnd) 1185 (103645) 2018-09-03 06:05:00
#36 sarah b (silva) 1168 (47847) 2018-11-28 11:38:47
#37 Karl Schutt (günter) 1167 (44374) 2018-11-30 22:19:10
#38 Luigi Tomelli (archstanton) 1164 (127538) 2018-12-19 16:17:47
#39 zuben c3 (zuben-c3) 1162 (27154) 2019-01-05 16:04:02
#40 Bertolo (Bertolo) 1160 (7167) 2019-01-15 18:34:32
#41 Clemens (16dombrowski) 1153 (5136) 2019-03-13 19:42:18
#42 Alex (Meiny) 1153 (5136) 2019-03-13 20:00:00
#43 Eugene (lim0n) 1144 (178540) 2019-06-22 15:29:12
#44 Bart den Hartog (Bart13) 1142 (148936) 2019-07-16 03:33:56
#45 Gerd Wilts (gerdw) 1142 (50534) 2019-07-16 07:43:05
#46 Alain Terieur (Alain) 1134 (6510) 2019-11-08 19:33:52
#47 Jasmin (Miles) 1134 (8987) 2019-11-09 01:28:15
#48 Derek Hatton (alfred_noble) 1130 (33998) 2020-01-28 22:46:49
#49 Thomas (Thomas4897) 1128 (36141) 2020-03-05 20:29:10
#50 Anabel Roschmann (Beltiona Mousa) 1127 (4919) 2020-03-24 02:55:19
#51 Polaris (Polaris) 1119 (32963) 2020-09-27 15:25:11
#52 Mike (RogueRamblers) 1118 (75961) 2020-11-11 18:32:54
#53 gordon (sir5) 1113 (16181) 2021-04-11 12:40:44
#54 Michael (FoM) 1113 (57794) 2021-04-18 13:39:59
#55 Silvia Kortmann (mikinsget) 1113 (20341) 2021-04-18 14:58:41
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Advent Challenge — Part 3

[rotthaler-05] - 38 users already solved this challenge, 2 are working on it.
 
 
 

What do you do, if your father and your stepmother decide to communicate only encrypted? You tape-record the messages. But what do the two of them really talk about?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-12-22 18:19
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#38) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 2000 (169444) 2017-12-22 19:30:50
Dominik M. (Sgt. Pepper) 2000 (128575) 2017-12-22 19:31:05
Alain Collignon (vexilla72) 2000 (123666) 2017-12-22 19:34:58
Kurt Gebauer (Yokozuna) 2000 (282608) 2017-12-22 19:43:48
#5 D3d4lu5 (D3d4lu5) 2000 (363488) 2017-12-22 19:44:19
#6 H. Lautenschlager (helmi) 2000 (56470) 2017-12-22 21:36:12
#7 Snake (snk) 2000 (187783) 2017-12-22 21:41:17
#8 Mir Dim (mir0soft) 2000 (79760) 2017-12-23 08:43:02
#9 S Combes (jerva) 2000 (242717) 2017-12-23 10:37:20
#10 Armin Krauss (argh) 1824 (206965) 2017-12-23 21:23:45
#11 Em Doulgerakis (Greko) 1824 (193799) 2017-12-24 12:12:44
#12 Rainer Zufall (kiekuk) 1576 (56786) 2017-12-28 16:21:44
#13 Ronja (Ronja) 1576 (3715) 2017-12-28 17:00:41
#14 E.T (Ertheb) 1456 (81809) 2018-01-03 17:42:31
#15 Nicolas (nicosPavlov) 1444 (257791) 2018-01-04 07:56:07
#16 Martin (martinbucher) 1423 (38365) 2018-01-06 11:17:17
#17 Manu (manu87) 1276 (2979) 2018-02-16 12:32:20
#18 Szabó Zoltán (szabo.z87) 1226 (55604) 2018-04-09 15:31:39
#19 Alain (Integral) 1192 (207924) 2018-06-24 23:40:15
#20 George (Theofanidis) 1190 (123216) 2018-07-02 22:33:10
#21 Random Dude (rnd) 1169 (103645) 2018-10-06 14:31:34
#22 Hans Peter (hanspeter) 1163 (52356) 2018-11-08 18:58:36
#23 Luigi Tomelli (archstanton) 1158 (127538) 2018-12-18 09:34:04
#24 Kasia (kasia-tutej) 1156 (53366) 2019-01-01 23:38:24
#25 zuben c3 (zuben-c3) 1156 (27154) 2019-01-03 20:45:49
#26 Eugene (lim0n) 1145 (178540) 2019-04-20 21:09:23
#27 Lane Williams (planetlane) 1144 (34637) 2019-05-04 03:53:34
#28 Bart den Hartog (Bart13) 1138 (148936) 2019-07-17 03:37:43
#29 Artur Puzio (cytadela8) 1118 (14801) 2020-09-21 11:12:37
#30 Polaris (Polaris) 1118 (32963) 2020-09-28 01:12:19
#31 Derek Hatton (alfred_noble) 1117 (33998) 2020-10-25 13:45:27
#32 Nicky (Wokini) 1116 (18494) 2020-11-11 15:22:07
#33 Flo (sealth) 1116 (25734) 2020-11-15 14:11:55
#34 Claude Vaillancourt (Cl3v3r) 1116 (44129) 2020-12-08 03:48:12
#35 Silvia Kortmann (mikinsget) 1115 (20341) 2020-12-26 14:21:16
#36 madness (madness) 1113 (71592) 2021-02-26 03:03:36
#37 Marco Cinelli (Snap) 1112 (37769) 2021-05-04 17:57:01
#38 Eric (ExAstris) 1111 (54941) 2021-05-18 18:53:31
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Advent Challenge — Part 4

[rotthaler-06] - 36 users already solved this challenge.
 
 
 

Decrypting a Christmas carol to help children in need? It's not that easy, if you don't know much about cryptography. Can you help Jacob and the children?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-12-21 17:06
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#36) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 2000 (169444) 2017-12-21 18:47:44
Michael Möller (michaelm) 2000 (253196) 2017-12-21 19:14:17
Kurt Gebauer (Yokozuna) 2000 (282608) 2017-12-21 19:56:48
S Combes (jerva) 2000 (242717) 2017-12-21 22:27:59
#5 H. Lautenschlager (helmi) 2000 (56470) 2017-12-21 23:30:50
#6 Dominik M. (Sgt. Pepper) 2000 (128575) 2017-12-22 01:43:42
#7 Alain Collignon (vexilla72) 2000 (123666) 2017-12-22 08:16:18
#8 D3d4lu5 (D3d4lu5) 1824 (363488) 2017-12-22 20:43:46
#9 Ronja (Ronja) 1824 (3715) 2017-12-22 22:59:42
#10 J-L Morel (Rossignol) 1824 (42130) 2017-12-23 09:15:19
#11 Mir Dim (mir0soft) 1824 (79760) 2017-12-23 11:56:52
#12 Armin Krauss (argh) 1725 (206965) 2017-12-23 23:50:55
#13 Rainer Zufall (kiekuk) 1547 (56786) 2017-12-28 14:16:36
#14 Snake (snk) 1502 (187783) 2017-12-29 21:06:52
#15 Nicolas (nicosPavlov) 1433 (257791) 2018-01-04 07:57:46
#16 E.T (Ertheb) 1423 (81809) 2018-01-04 18:37:28
#17 George (Theofanidis) 1302 (123216) 2018-01-31 18:24:56
#18 Nofre Tete (noffi) 1229 (26507) 2018-04-02 11:48:23
#19 Szabó Zoltán (szabo.z87) 1223 (55604) 2018-04-12 12:01:01
#20 Alain (Integral) 1192 (207924) 2018-06-24 18:18:23
#21 Eric (ExAstris) 1192 (54941) 2018-06-24 21:14:31
#22 Em Doulgerakis (Greko) 1181 (193799) 2018-08-02 16:48:27
#23 Hans Joachim Girulat (joregi) 1178 (36278) 2018-08-18 18:12:23
#24 Random Dude (rnd) 1168 (103645) 2018-10-06 04:22:09
#25 Luigi Tomelli (archstanton) 1158 (127538) 2018-12-18 14:22:13
#26 Kasia (kasia-tutej) 1156 (53366) 2019-01-01 23:18:27
#27 Lane Williams (planetlane) 1149 (34637) 2019-03-08 02:58:17
#28 Eugene (lim0n) 1145 (178540) 2019-04-21 12:39:25
#29 Bart den Hartog (Bart13) 1138 (148936) 2019-07-17 17:45:13
#30 Polaris (Polaris) 1118 (32963) 2020-09-29 23:10:52
#31 Derek Hatton (alfred_noble) 1117 (33998) 2020-10-27 12:56:32
#32 Flo (sealth) 1116 (25734) 2020-11-15 17:38:24
#33 zuben c3 (zuben-c3) 1116 (27154) 2020-11-20 11:00:17
#34 Nicky (Wokini) 1116 (18494) 2020-12-02 09:42:38
#35 Claude Vaillancourt (Cl3v3r) 1116 (44129) 2020-12-09 16:49:19
#36 madness (madness) 1113 (71592) 2021-02-26 03:22:17
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AES ECB Wrong Encoding

[miro-01] - 20 users already solved this challenge.
 
 
 

Do you believe that AES is easy to break because of a wrong encoding? Try it yourself...
Read more...

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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-12-16 19:21
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#20) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 2000 (169444) 2017-12-17 18:10:22
Snake (snk) 1824 (187783) 2017-12-17 21:48:12
Armin Krauss (argh) 1824 (206965) 2017-12-17 23:34:09
Kurt Gebauer (Yokozuna) 1824 (282608) 2017-12-18 13:16:26
#5 Kasia (kasia-tutej) 1613 (53366) 2017-12-21 16:40:57
#6 D3d4lu5 (D3d4lu5) 1523 (363488) 2017-12-24 04:30:18
#7 Dominik M. (Sgt. Pepper) 1523 (128575) 2017-12-24 17:46:24
#8 H. Lautenschlager (helmi) 1423 (56470) 2017-12-31 18:15:33
#9 a (agigi) 1192 (1192) 2018-06-18 14:46:05
#10 Oprea Bogdan (bogdan.oprea) 1192 (1192) 2018-06-18 14:48:57
#11 Teodoru catalin Andrei (teodoru) 1192 (5698) 2018-06-20 15:55:25
#12 Alain (Integral) 1184 (207924) 2018-07-19 09:43:49
#13 Em Doulgerakis (Greko) 1180 (193799) 2018-08-03 11:01:50
#14 Eugene (lim0n) 1143 (178540) 2019-05-12 06:23:52
#15 Bart den Hartog (Bart13) 1130 (148936) 2019-11-20 13:25:33
#16 madness (madness) 1126 (71592) 2020-02-28 17:34:49
#17 Silvia Kortmann (mikinsget) 1120 (20341) 2020-07-26 01:55:57
#18 Claude Vaillancourt (Cl3v3r) 1112 (44129) 2021-04-14 18:27:26
#19 Luigi Tomelli (archstanton) 1111 (127538) 2021-05-20 17:54:45
#20 Eric (ExAstris) 1111 (54941) 2021-05-21 01:31:06
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Advent-Challenge — Part 2

[rotthaler-04] - 45 users already solved this challenge, 2 are working on it.
 
 
 

Mike would like to belong to the cryptographers. Can you help him to find out their meeting point at the Christmas market?
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-12-16 19:20
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#45) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2017-12-17 00:20:59
Dominik M. (Sgt. Pepper) 2000 (128575) 2017-12-17 06:30:45
Alain Collignon (vexilla72) 2000 (123666) 2017-12-17 11:20:39
Viktor (Veselovský) 2000 (169444) 2017-12-17 12:30:11
#5 Snake (snk) 2000 (187783) 2017-12-17 13:08:04
#6 HolgerK (HolgerK) 1824 (25776) 2017-12-17 21:40:33
#7 Armin Krauss (argh) 1824 (206965) 2017-12-17 23:35:23
#8 H. Lautenschlager (helmi) 1824 (56470) 2017-12-18 16:07:50
#9 Em Doulgerakis (Greko) 1824 (193799) 2017-12-18 16:55:03
#10 Rainer Zufall (kiekuk) 1725 (56786) 2017-12-19 18:36:20
#11 Mir Dim (mir0soft) 1660 (79760) 2017-12-20 14:38:38
#12 J-L Morel (Rossignol) 1660 (42130) 2017-12-20 15:48:19
#13 Kasia (kasia-tutej) 1613 (53366) 2017-12-21 14:27:23
#14 Martin (martinbucher) 1613 (38365) 2017-12-21 16:34:55
#15 D3d4lu5 (D3d4lu5) 1576 (363488) 2017-12-22 14:54:56
#16 chris_3stones (3stones) 1469 (38845) 2017-12-26 20:14:01
#17 George (Theofanidis) 1469 (123216) 2017-12-26 20:17:25
#18 T (Wagner) 1433 (16988) 2017-12-30 08:51:23
#19 Nicolas (nicosPavlov) 1414 (257791) 2018-01-01 12:24:40
#20 E.T (Ertheb) 1406 (81809) 2018-01-02 18:16:51
#21 j.h. (haegarq) 1357 (15352) 2018-01-10 11:36:25
#22 Tristan1473 (Tristan1473) 1260 (20432) 2018-02-22 09:28:54
#23 Thomas Gonda (TomG) 1236 (36291) 2018-03-19 14:50:31
#24 Szabó Zoltán (szabo.z87) 1222 (55604) 2018-04-09 12:22:19
#25 Silvia Kortmann (mikinsget) 1203 (20341) 2018-05-17 01:25:36
#26 Hans Joachim Girulat (joregi) 1177 (36278) 2018-08-16 23:28:02
#27 Random Dude (rnd) 1168 (103645) 2018-10-04 15:41:41
#28 Hans Peter (hanspeter) 1162 (52356) 2018-11-08 18:57:23
#29 Luigi Tomelli (archstanton) 1157 (127538) 2018-12-17 18:06:55
#30 zuben c3 (zuben-c3) 1155 (27154) 2019-01-02 12:17:53
#31 Eugene (lim0n) 1144 (178540) 2019-04-20 21:06:17
#32 Bart den Hartog (Bart13) 1138 (148936) 2019-07-17 02:45:34
#33 David (dvd) 1128 (3813) 2020-01-05 22:00:38
#34 Lane Williams (planetlane) 1120 (34637) 2020-07-14 18:41:23
#35 Artur Puzio (cytadela8) 1118 (14801) 2020-09-21 11:03:52
#36 Polaris (Polaris) 1117 (32963) 2020-10-04 01:30:14
#37 Derek Hatton (alfred_noble) 1117 (33998) 2020-10-25 01:43:08
#38 Nicky (Wokini) 1116 (18494) 2020-11-11 09:31:15
#39 Flo (sealth) 1116 (25734) 2020-11-15 13:41:42
#40 Michael (FoM) 1116 (57794) 2020-12-06 00:28:43
#41 Claude Vaillancourt (Cl3v3r) 1115 (44129) 2020-12-22 19:24:09
#42 Jean-Francois (Muskrat) 1115 (19013) 2021-01-04 15:29:40
#43 Hank (hanky) 1114 (24373) 2021-02-03 15:20:05
#44 madness (madness) 1113 (71592) 2021-02-26 00:19:33
#45 Marco Cinelli (Snap) 1111 (37769) 2021-05-04 10:03:45
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Hilly — Part 2

[almardeny-02] - 1 user already solved this challenge, 1 is working on it.
 
 
 

Hilly is an improved version of Hill cipher. This challenge consists of the decryption of a ciphertext by means of a partly-known key.
Read more...

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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-10-17 17:12
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#1) Achieved points (Global score) y-m-d - h:m:s

Em Doulgerakis (Greko) 1156 (193799) 2018-10-29 21:19:05
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Weakened ElsieFour — Part 3

[rotthaler-02] - 3 users already solved this challenge.
 
 
 

The challenges for the weakened ElsieFour serve as an exercise and use an intentionally weakened version of LC4. ElsieFour combines ideas of modern RC4 stream cipher, historical Playfair cipher and plaintext-dependent keystreams. It can be computed manually. Part 3 is a partly-known-plaintext challenge which provides 2 messages that were encrypted with the same key.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-10-03 06:39
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Nicolas (nicosPavlov) 1226 (257791) 2018-01-18 01:49:20
Michael Möller (michaelm) 1186 (253196) 2018-04-24 07:26:39
D3d4lu5 (D3d4lu5) 1113 (363488) 2020-12-29 19:34:27
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Kaskade-S/T — Part 6 (RansomKaskade Part 1)

[mirkobe-01] - 6 users already solved this challenge.
 
 
 

From a honeypot you get a set of encrypted files and the according plaintext files. Could you discover the used key, to help victims of the ransom ware?
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Authors: This email address is being protected from spambots. You need JavaScript enabled to view it.,This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-07-02 12:32
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#6) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 1444 (206965) 2017-07-14 14:00:35
Michael Möller (michaelm) 1344 (253196) 2017-07-29 12:39:20
Kurt Gebauer (Yokozuna) 1186 (282608) 2018-01-22 18:16:47
George Lasry (george4096) 1156 (399565) 2018-07-08 22:27:49
#5 Alain Collignon (vexilla72) 1142 (123666) 2018-12-02 20:00:09
#6 D3d4lu5 (D3d4lu5) 1131 (363488) 2019-05-19 12:39:50
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Holographic Encryption — Part 2

[pavillon-02] - 3 users already solved this challenge.
 
 
 

Holographic encryption can be performed by employing encryption masks which alter the field before propagation. This makes the image
unrecognizable when recorded. You are given three holograms that represent the cipher image and three plain images and their holograms which were encrypted with the same encryption masks.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-04-07 22:29
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 1613 (169444) 2017-04-12 18:46:17
Armin Krauss (argh) 1444 (206965) 2017-04-20 17:54:38
Eugene (lim0n) 1120 (178540) 2019-11-16 13:49:41
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Holographic Encryption — Part 1

[pavillon-01] - 6 users already solved this challenge.
 
 
 

Holographic encryption can be performed by employing encryption masks which alter the field before propagation. This makes the image unrecognizable when recorded. You are given three holograms that represent the cipher image and two corrupted encryption masks.
Read more...

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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-04-07 22:25
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#6) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 1660 (169444) 2017-04-11 09:41:56
Armin Krauss (argh) 1456 (206965) 2017-04-19 17:59:59
Bart den Hartog (Bart13) 1198 (148936) 2017-09-20 03:18:52
D3d4lu5 (D3d4lu5) 1124 (363488) 2019-07-21 16:07:09
#5 Eugene (lim0n) 1120 (178540) 2019-11-08 18:32:36
#6 Kurt Gebauer (Yokozuna) 1117 (282608) 2020-02-03 08:16:13
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Hilly — Part 1

[almardeny-01] - 9 users already solved this challenge, 5 are working on it.
 
 
 

Hilly is an improved version of the Hill cipher. This challenge consists of the decryption of a ciphertext by means of a given plaintext-ciphertext pair.
Read more...

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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2017-01-25 04:09
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#9) Achieved points (Global score) y-m-d - h:m:s

Viktor (Veselovský) 1385 (169444) 2017-02-13 19:33:24
Dominik M. (Sgt. Pepper) 1142 (128575) 2018-07-03 02:17:21
Alain (Integral) 1142 (207924) 2018-07-03 19:30:44
Alain Collignon (vexilla72) 1141 (123666) 2018-07-14 09:53:00
#5 Em Doulgerakis (Greko) 1139 (193799) 2018-08-07 11:17:55
#6 D3d4lu5 (D3d4lu5) 1127 (363488) 2019-03-06 17:05:47
#7 Eugene (lim0n) 1120 (178540) 2019-09-04 14:38:53
#8 Bart den Hartog (Bart13) 1119 (148936) 2019-09-19 07:08:40
#9 Kurt Gebauer (Yokozuna) 1104 (282608) 2021-06-05 12:12:23
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ASAC — A Strong(er) ADFGVX Cipher — Part 5

[fendt-05] - 0 users already solved this challenge.
 
 
 

This series consists of 5 challenges based on each other. It introduces a new three-step cipher called ASAC, which is a modified version of ADFGVX. Part 5 is a "bonus" and just modifies the second challenge of this series by improving the second step of the cipher.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2016-07-09 19:15
Maximum number of attempts for this challenge: 15

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ASAC — A Strong(er) ADFGVX Cipher — Part 4

[fendt-04] - 0 users already solved this challenge.
 
 
 

This series consists of 5 challenges based on each other. It introduces a new three-step cipher called ASAC, which is a modified version of ADFGVX. Part 4 uses the complete cipher and is the main challenge of this series.
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Published on: 2016-07-09 19:13
Maximum number of attempts for this challenge: 15

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ASAC — A Strong(er) ADFGVX Cipher — Part 3

[fendt-03] - 0 users already solved this challenge.
 
 
 

This series consists of 5 challenges based on each other. It introduces a new three-step cipher called ASAC, which is a modified version of ADFGVX. Part 3 involves the complete cipher but weakens the third step by using a single-column transposition instead of a double column transposition.
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Published on: 2016-07-09 19:10
Maximum number of attempts for this challenge: 15

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ASAC — A Strong(er) ADFGVX Cipher — Part 2

[fendt-02] - 1 user already solved this challenge.
 
 
 

This series consists of 5 challenges based on each other. It introduces a new three-step cipher called ASAC, which is a modified version of ADFGVX. Part 2 uses only the first two steps of the cipher.
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Published on: 2016-07-09 19:08
Maximum number of attempts for this challenge: 15

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Rank User (#1) Achieved points (Global score) y-m-d - h:m:s

George Lasry (george4096) 1155 (399565) 2017-08-01 00:01:51
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ASAC — A Strong(er) ADFGVX Cipher — Part 1

[fendt-01] - 16 users already solved this challenge, 1 is working on it.
 
 
 

This series consists of 5 challenges based on each other. It introduces a new three-step cipher called ASAC, which is a modified version of ADFGVX. Part 1 is meant as an introduction and uses only the first step of ASAC.
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Published on: 2016-07-09 19:05
Maximum number of attempts for this challenge: 15

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Rank User (#16) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 2000 (206965) 2016-07-09 20:51:02
zahir mohsen moradi (ariobarzan) 2000 (99757) 2016-07-09 23:39:20
Snake (snk) 2000 (187783) 2016-07-10 18:57:24
Robert (rm) 1613 (56475) 2016-07-13 20:20:15
#5 Kurt Gebauer (Yokozuna) 1613 (282608) 2016-07-13 20:55:56
#6 Alain (Integral) 1576 (207924) 2016-07-15 09:41:37
#7 Julia Bernotat (El Greco ) 1433 (81129) 2016-07-23 00:33:55
#8 Em Doulgerakis (Greko) 1266 (193799) 2016-09-10 08:42:36
#9 Marc (rcll0891) 1204 (24004) 2016-12-05 19:50:21
#10 Alain Collignon (vexilla72) 1204 (123666) 2016-12-06 16:18:38
#11 Danny Higgins (hamster147) 1179 (39638) 2017-02-26 18:09:02
#12 George Lasry (george4096) 1155 (399565) 2017-07-31 21:27:03
#13 D3d4lu5 (D3d4lu5) 1152 (363488) 2017-08-22 18:15:07
#14 Bart den Hartog (Bart13) 1143 (148936) 2017-11-29 00:40:19
#15 Eugene (lim0n) 1108 (178540) 2020-04-25 16:41:52
#16 Dominik M. (Sgt. Pepper) 1101 (128575) 2021-05-08 16:25:36
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Weakened Handycipher — Part 6

[kallick-20] - 5 users already solved this challenge.
 
 
 

The Weakened Handycipher challenges serve as an exercise and use an intentionally weakened version of Handycipher. Part 6 is the same as Part 3, but uses an improved version of the cipher. It is ciphertext-only.
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Published on: 2016-06-28 20:12
Maximum number of attempts for this challenge: 15

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Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Alain (Integral) 1307 (207924) 2016-08-07 12:09:26
Michael Möller (michaelm) 1292 (253196) 2016-08-14 17:29:02
George Lasry (george4096) 1161 (399565) 2017-05-29 01:02:28
Nicolas (nicosPavlov) 1136 (257791) 2018-02-18 11:22:27
#5 D3d4lu5 (D3d4lu5) 1123 (363488) 2018-11-01 00:50:59
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Weakened Handycipher — Part 5

[kallick-19] - 5 users already solved this challenge.
 
 
 

The Weakened Handycipher challenges serve as an exercise and use an intentionally weakened version of Handycipher. Part 5 is the same as Part 2, but uses an improved version of the cipher. It is ciphertext-only, but you are given some partial information about the key.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2016-06-28 20:10
Maximum number of attempts for this challenge: 15

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Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Michael Möller (michaelm) 1337 (253196) 2016-07-28 16:36:55
Alain (Integral) 1310 (207924) 2016-08-06 16:25:46
George Lasry (george4096) 1161 (399565) 2017-05-29 21:15:02
Nicolas (nicosPavlov) 1136 (257791) 2018-02-18 11:18:20
#5 D3d4lu5 (D3d4lu5) 1123 (363488) 2018-10-31 22:03:45
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Weakened Handycipher — Part 4

[kallick-18] - 5 users already solved this challenge.
 
 
 

The Weakened Handycipher challenges serve as an exercise and use an intentionally weakened version of Handycipher. Part 4 is the same as Part 1, but uses an improved version of the cipher. You are given the first 1,009 characters of the plaintext, and some partial information about the key.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2016-06-28 20:08
Maximum number of attempts for this challenge: 15

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Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Michael Möller (michaelm) 1414 (253196) 2016-07-13 21:09:45
Alain (Integral) 1310 (207924) 2016-08-06 14:10:50
George Lasry (george4096) 1161 (399565) 2017-05-30 16:00:56
Nicolas (nicosPavlov) 1137 (257791) 2018-02-12 14:08:00
#5 D3d4lu5 (D3d4lu5) 1124 (363488) 2018-10-31 06:18:10
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New Year's Greetings — Part 5

[gutgesell-05] - 15 users already solved this challenge, 1 is working on it.
 
 
 

This series consists of five parts which are based on each other and that will be getting more and more complicated with each part. This is the last part and teaches us something about the weaknesses of this method by improving it a little bit in some points.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2016-03-21 10:05
Maximum number of attempts for this challenge: 15

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Rank User (#15) Achieved points (Global score) y-m-d - h:m:s

Szabó Zoltán (szabo.z87) 2000 (55604) 2016-03-21 19:18:08
Rainer Zufall (kiekuk) 1725 (56786) 2016-03-23 15:46:41
Viktor (Veselovský) 1576 (169444) 2016-03-26 13:20:45
Alain (Integral) 1502 (207924) 2016-03-29 14:51:54
#5 Bernhard Gruber (bgr) 1414 (22889) 2016-04-05 13:31:28
#6 Andreas Frerichs (Ossili) 1330 (33266) 2016-04-21 19:19:07
#7 zahir mohsen moradi (ariobarzan) 1330 (99757) 2016-04-21 21:37:32
#8 Christian (chrisadmin) 1212 (2019) 2016-07-31 14:45:51
#9 E.T (Ertheb) 1212 (81809) 2016-08-01 06:43:37
#10 Armin Krauss (argh) 1199 (206965) 2016-08-30 22:10:09
#11 Hans Peter (hanspeter) 1193 (52356) 2016-09-17 12:16:50
#12 D3d4lu5 (D3d4lu5) 1148 (363488) 2017-06-18 20:00:10
#13 Michael (FoM) 1117 (57794) 2019-02-02 09:30:42
#14 Dominik M. (Sgt. Pepper) 1115 (128575) 2019-03-25 13:53:22
#15 Derek Hatton (alfred_noble) 1107 (33998) 2020-02-18 00:58:18
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Weakened Granit — Part 3

[drobick-07] - 0 users already solved this challenge.
 
 
 

The challenges for the simplified GRANIT cipher, a method that can be done manually, serve as an exercise and use an intentionally simplified version of GRANIT.
Part 3 is a ciphertext-only challenge for which the second permutation key is known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-09-24 07:37
Maximum number of attempts for this challenge: 15

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Weakened Granit — Part 2

[drobick-06] - 0 users already solved this challenge, 1 is working on it.
 
 
 

The challenges for the simplified GRANIT cipher, a method that can be done manually, serve as an exercise and use an intentionally simplified version of GRANIT.
Part 2 is a ciphertext-only challenge for which the first permutation key is known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-09-24 07:34
Maximum number of attempts for this challenge: 15

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Spirale — Part 3

[allard-03] - 4 users already solved this challenge.
 
 
 

Spirale is a OTP cipher designed to be simply performed by hand.
Part 3 is a ciphertext-only challenge with a 949-letter ciphertext.
In this part, two of the four keys are equal to the keys of the first two parts.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-08-23 19:08
Maximum number of attempts for this challenge: 15

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Rank User (#4) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 1378 (242717) 2015-09-13 15:43:29
J-L Morel (Rossignol) 1143 (42130) 2017-01-19 15:27:30
George Lasry (george4096) 1129 (399565) 2017-08-21 21:46:21
D3d4lu5 (D3d4lu5) 1098 (363488) 2021-01-19 19:45:17
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Spirale — Part 2

[allard-02] - 5 users already solved this challenge.
 
 
 

Spirale is a OTP cipher designed to be simply performed by hand.
Part 2 is a ciphertext-only challenge with a 659-letter ciphertext.
This part uses the same four keys for encryption as part 1 does.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-08-23 19:05
Maximum number of attempts for this challenge: 15

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Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 1378 (242717) 2015-09-12 21:15:06
J-L Morel (Rossignol) 1143 (42130) 2017-01-19 15:23:12
George Lasry (george4096) 1129 (399565) 2017-08-21 21:06:46
Kurt Gebauer (Yokozuna) 1103 (282608) 2020-01-28 12:25:55
#5 D3d4lu5 (D3d4lu5) 1098 (363488) 2021-01-19 19:44:01
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Spirale — Part 1

[allard-01] - 5 users already solved this challenge, 2 are working on it.
 
 
 

Spirale is a OTP cipher designed to be simple to implement by hand. It is resilient to errors as they have only a local effect without obscuring all the ciphertext.
Part 1 is a partly-known plaintext challenge with a 314-letter ciphertext. The first 75 letters of the plaintext are known.
Part 2 of this series uses the same four keys as this one.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-08-23 19:04
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

S Combes (jerva) 1378 (242717) 2015-09-12 21:12:42
J-L Morel (Rossignol) 1143 (42130) 2017-01-19 15:14:20
George Lasry (george4096) 1129 (399565) 2017-08-21 20:56:27
Kurt Gebauer (Yokozuna) 1103 (282608) 2020-01-28 12:24:14
#5 D3d4lu5 (D3d4lu5) 1098 (363488) 2021-01-19 19:42:42
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Flawed Usage of a OTP Cipher by the BND

[drobick-04] - 14 users already solved this challenge.
 
 
 

During the cold war the foreign intelligence agency of Germany established so-called stay-behind units. Their radio messages were encrypted by a OTP method, but the keys were used multiple times.
This challenge is about the effect of this multiple usage on the security of the method. You are given 5 messages, all encrypted with the same key.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-08-23 19:00
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#14) Achieved points (Global score) y-m-d - h:m:s

Armin Krauss (argh) 1725 (206965) 2015-08-26 17:13:36
Kurt Gebauer (Yokozuna) 1576 (282608) 2015-08-28 22:20:36
Alain (Integral) 1456 (207924) 2015-09-04 16:37:12
Bart den Hartog (Bart13) 1398 (148936) 2015-09-10 14:30:56
#5 Julia Bernotat (El Greco ) 1337 (81129) 2015-09-21 21:32:23
#6 Robert (rm) 1292 (56475) 2015-10-08 21:06:29
#7 Matthias Kotzerke (Esdeath) 1182 (4004) 2016-03-30 19:45:17
#8 Em Doulgerakis (Greko) 1172 (193799) 2016-05-16 09:35:38
#9 Alain Collignon (vexilla72) 1152 (123666) 2016-10-10 18:28:06
#10 D3d4lu5 (D3d4lu5) 1130 (363488) 2017-08-08 22:49:04
#11 Nicolas (nicosPavlov) 1120 (257791) 2018-04-01 11:44:13
#12 Dominik M. (Sgt. Pepper) 1117 (128575) 2018-06-21 23:00:27
#13 Eugene (lim0n) 1106 (178540) 2019-09-28 17:08:21
#14 Polaris (Polaris) 1100 (32963) 2020-08-16 17:37:58
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Double-Column Transposition/Granit — Part 3

[drobick-03] - 0 users already solved this challenge.
 
 
 

This challenge series is about the GRANIT cipher, a method that can be done manually. It has been used for instance by the former GDR spy Günter Guillaume till about 1960.
Part 1, 2 and 3 of this series use the same keyword for generating the key matrix, but different permutation keys. This part has a ciphertext-only challenge and the ciphertext has 80 characters.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-07-01 18:23
Maximum number of attempts for this challenge: 10

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Double-Column Transposition/Granit — Part 2

[drobick-02] - 0 users already solved this challenge.
 
 
 

This challenge series is about the GRANIT cipher, a method that can be done manually. It has been used for instance by the former GDR spy Günter Guillaume till about 1960.
Part 1, 2 and 3 of this series use the same keyword for generating the key matrix, but different permutation keys. This part has a ciphertext-only challenge and the ciphertext has 110 characters.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-07-01 18:21
Maximum number of attempts for this challenge: 15

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Double-Column Transposition/Granit — Part 1

[drobick-01] - 0 users already solved this challenge, 2 are working on it.
 
 
 

This challenge series is about the GRANIT cipher, a method that can be done manually. It has been used for instance by the former GDR spy Günter Guillaume till about 1960.
Part 1, 2 and 3 of this series use the same keyword for generating the key matrix, but different permutation keys. In this part a codebook is used additionally, and the given ciphertext has 70 characters.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-07-01 18:20
Maximum number of attempts for this challenge: 15

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Weakened Handycipher — Part 3

[kallick-11] - 14 users already solved this challenge, 1 is working on it.
 
 
 

The challenges for the weakened Handycipher serve as an exercise and use an intentionally weakened version of Handycipher. Part 3 is a ciphertext-only challenge.
Handycipher is a newly designed cipher to permit pen-and-paper encrypting and decrypting, while providing a significantly high level of security.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-05-13 11:49
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#14) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2015-05-13 21:52:11
Armin Krauss (argh) 1576 (206965) 2015-05-18 14:55:24
Julia Bernotat (El Greco ) 1485 (81129) 2015-05-23 00:58:36
S Combes (jerva) 1444 (242717) 2015-05-26 08:31:39
#5 Alain (Integral) 1357 (207924) 2015-06-07 10:32:44
#6 zahir mohsen moradi (ariobarzan) 1216 (99757) 2015-09-14 18:27:06
#7 Michael Möller (michaelm) 1216 (253196) 2015-09-14 18:54:08
#8 Em Doulgerakis (Greko) 1152 (193799) 2016-06-24 14:59:34
#9 George Lasry (george4096) 1128 (399565) 2017-05-27 03:40:02
#10 Nicolas (nicosPavlov) 1119 (257791) 2018-01-23 02:27:58
#11 D3d4lu5 (D3d4lu5) 1111 (363488) 2018-10-27 06:27:48
#12 Viktor (Veselovský) 1108 (169444) 2019-02-22 23:32:41
#13 Danny Higgins (hamster147) 1106 (39638) 2019-05-08 16:05:36
#14 Random Dude (rnd) 1106 (103645) 2019-06-15 03:11:22
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Weakened Handycipher — Part 2

[kallick-10] - 13 users already solved this challenge.
 
 
 

The challenges for the weakened Handycipher serve as an exercise and use an intentionally weakened version of Handycipher. Part 2 is a ciphertext-only challenge with a helping additional information.
Handycipher is a newly designed cipher to permit pen-and-paper encrypting and decrypting, while providing a significantly high level of security.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-05-13 11:48
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#13) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2015-05-13 16:00:48
Armin Krauss (argh) 1523 (206965) 2015-05-21 01:33:08
Julia Bernotat (El Greco ) 1502 (81129) 2015-05-21 18:04:20
Alain (Integral) 1357 (207924) 2015-06-06 13:54:36
#5 Michael Möller (michaelm) 1220 (253196) 2015-09-08 05:32:57
#6 zahir mohsen moradi (ariobarzan) 1216 (99757) 2015-09-14 18:26:02
#7 Em Doulgerakis (Greko) 1155 (193799) 2016-05-31 12:37:35
#8 George Lasry (george4096) 1128 (399565) 2017-05-27 03:33:02
#9 Nicolas (nicosPavlov) 1119 (257791) 2018-01-22 11:41:35
#10 D3d4lu5 (D3d4lu5) 1111 (363488) 2018-10-27 06:26:19
#11 Viktor (Veselovský) 1108 (169444) 2019-02-22 18:57:23
#12 Danny Higgins (hamster147) 1107 (39638) 2019-05-06 18:37:41
#13 Random Dude (rnd) 1106 (103645) 2019-06-14 00:42:27
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Weakened Handycipher — Part 1

[kallick-09] - 15 users already solved this challenge.
 
 
 

The challenges for the weakened Handycipher serve as an exercise and use an intentionally weakened version of Handycipher. Part 1 is a partially-known-plaintext challenge with a helping additional information.
Handycipher is a newly designed cipher to permit pen-and-paper encrypting and decrypting, while providing a significantly high level of security.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-05-13 11:47
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#15) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2015-05-13 12:44:32
Julia Bernotat (El Greco ) 1613 (81129) 2015-05-17 18:02:13
Armin Krauss (argh) 1485 (206965) 2015-05-22 19:32:50
Alain (Integral) 1362 (207924) 2015-06-05 15:01:59
#5 Michael Möller (michaelm) 1235 (253196) 2015-08-15 16:25:41
#6 zahir mohsen moradi (ariobarzan) 1229 (99757) 2015-08-22 12:40:27
#7 Karl Schutt (günter) 1167 (44374) 2016-03-07 05:20:49
#8 Em Doulgerakis (Greko) 1156 (193799) 2016-05-18 13:14:59
#9 George Lasry (george4096) 1128 (399565) 2017-05-28 22:01:31
#10 Nicolas (nicosPavlov) 1119 (257791) 2018-01-19 02:26:13
#11 D3d4lu5 (D3d4lu5) 1111 (363488) 2018-10-26 07:56:33
#12 Viktor (Veselovský) 1108 (169444) 2019-02-22 19:24:31
#13 Snake (snk) 1108 (187783) 2019-03-06 13:55:44
#14 Danny Higgins (hamster147) 1107 (39638) 2019-05-02 09:21:44
#15 Random Dude (rnd) 1106 (103645) 2019-06-25 00:12:17
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Extended Handycipher — Part 3

[kallick-06] - 3 users already solved this challenge, 1 is working on it.
 
 
 

Extended Handycipher is an enhancement of the newly designed cipher Handycipher, which permits pen-and-paper encrypting and decrypting, while providing a significantly high level of security. You got only two different ciphertexts of the 996-character plaintext.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-03-27 15:28
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Michael Möller (michaelm) 1183 (253196) 2015-10-31 18:28:20
George Lasry (george4096) 1126 (399565) 2017-05-31 10:24:36
D3d4lu5 (D3d4lu5) 1109 (363488) 2018-11-16 17:12:39
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Extended Handycipher — Part 2

[kallick-05] - 3 users already solved this challenge.
 
 
 

Extended Handycipher is an enhancement of the newly designed cipher Handycipher, which permits pen-and-paper encrypting and decrypting, while providing a significantly high level of security. From the 905-character plaintext 229 characters somewhere in it are known.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-03-27 15:27
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Michael Möller (michaelm) 1185 (253196) 2015-10-23 09:07:20
George Lasry (george4096) 1126 (399565) 2017-05-31 10:18:56
D3d4lu5 (D3d4lu5) 1109 (363488) 2018-11-13 20:07:14
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Extended Handycipher — Part 1

[kallick-04] - 3 users already solved this challenge, 1 is working on it.
 
 
 

Extended Handycipher is an enhancement of the newly designed cipher Handycipher, which permits pen-and-paper encrypting and decrypting, while providing a significantly high level of security. From the 815-character plaintext the first 229 characters are known.
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-03-27 15:26
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#3) Achieved points (Global score) y-m-d - h:m:s

Michael Möller (michaelm) 1192 (253196) 2015-09-27 11:51:38
George Lasry (george4096) 1126 (399565) 2017-05-31 10:23:02
D3d4lu5 (D3d4lu5) 1109 (363488) 2018-11-10 17:59:52
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Handycipher — Part 2

[kallick-02] - 7 users already solved this challenge.
 
 
 

Handycipher is a newly designed cipher to permit pen-and-paper encrypting and decrypting, while providing a significantly high level of security. From the 1142-character plaintext 229 characters somewhere in it are known.
Read more...

Click here to get to the corresponding forum topic to share your opinion.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-03-03 23:34
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#7) Achieved points (Global score) y-m-d - h:m:s

Alain (Integral) 1232 (207924) 2015-06-09 23:28:30
Michael Möller (michaelm) 1187 (253196) 2015-09-20 13:16:49
Em Doulgerakis (Greko) 1140 (193799) 2016-09-06 10:35:51
George Lasry (george4096) 1125 (399565) 2017-05-27 01:48:16
#5 Nicolas (nicosPavlov) 1116 (257791) 2018-01-30 02:15:53
#6 D3d4lu5 (D3d4lu5) 1109 (363488) 2018-11-01 19:59:30
#7 Random Dude (rnd) 1104 (103645) 2019-07-21 17:29:33
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Handycipher — Part 1

[kallick-01] - 5 users already solved this challenge, 4 are working on it.
 
 
 

Handycipher is a newly designed cipher to permit pen-and-paper encrypting and decrypting, while providing a significantly high level of security. From the 858-character plaintext the first 229 characters are known.
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
Click here to download the additional file of the challenge.

Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2015-03-03 23:33
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#5) Achieved points (Global score) y-m-d - h:m:s

Alain (Integral) 1233 (207924) 2015-06-08 17:49:57
Michael Möller (michaelm) 1188 (253196) 2015-09-19 21:09:57
George Lasry (george4096) 1125 (399565) 2017-05-27 01:43:42
Nicolas (nicosPavlov) 1116 (257791) 2018-01-30 05:42:58
#5 D3d4lu5 (D3d4lu5) 1109 (363488) 2018-11-01 17:41:29
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M-138 — Part 4

[schmeh-12] - 25 users already solved this challenge, 1 is working on it.
 
 
 

This is part 4 in a series about the M-138. Part 4 is a ciphertext-only challenge (75 letters).
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2014-12-24 00:34
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#25) Achieved points (Global score) y-m-d - h:m:s

Kurt Gebauer (Yokozuna) 2000 (282608) 2014-12-24 12:41:00
Michael Möller (michaelm) 1367 (253196) 2015-01-15 21:25:39
Claude Vaillancourt (Cl3v3r) 1264 (44129) 2015-02-26 17:40:02
E.T (Ertheb) 1228 (81809) 2015-04-06 09:11:56
#5 Alain (Integral) 1178 (207924) 2015-08-17 13:42:22
#6 Julia Bernotat (El Greco ) 1149 (81129) 2016-03-10 21:26:18
#7 Norbert Biermann (Norbert) 1135 (47790) 2016-08-30 20:44:31
#8 Bart den Hartog (Bart13) 1127 (148936) 2017-01-31 14:56:08
#9 George Lasry (george4096) 1122 (399565) 2017-05-24 09:45:52
#10 Armin Krauss (argh) 1122 (206965) 2017-06-06 21:20:09
#11 Mir Dim (mir0soft) 1122 (79760) 2017-06-11 20:24:18
#12 D3d4lu5 (D3d4lu5) 1112 (363488) 2018-04-23 12:52:12
#13 Dominik M. (Sgt. Pepper) 1110 (128575) 2018-07-17 21:55:20
#14 Random Dude (rnd) 1108 (103645) 2018-10-08 19:11:39
#15 Luigi Tomelli (archstanton) 1106 (127538) 2018-12-24 09:17:25
#16 Benjamin (200611736) 1105 (10186) 2019-03-24 19:00:30
#17 Snake (snk) 1097 (187783) 2020-08-05 15:49:38
#18 lakis (lakis) 1095 (3366) 2021-01-27 23:12:13
#19 sarah b (silva) 1095 (47847) 2021-02-17 14:02:59
#20 Martin (martinbucher) 1094 (38365) 2021-03-15 15:31:27
#21 Somebody (Achidutzu) 1094 (14883) 2021-03-19 22:22:09
#22 George (Theofanidis) 1094 (123216) 2021-03-21 23:21:58
#23 Lane Williams (planetlane) 1094 (34637) 2021-04-10 21:42:29
#24 Michael (FoM) 1094 (57794) 2021-04-26 15:51:38
#25 Eric (ExAstris) 1094 (54941) 2021-05-05 05:08:15
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M-138 — Part 3

[schmeh-11] - 57 users already solved this challenge, 4 are working on it.
 
 
 

This is part 3 in a series about the M-138. Part 3 is a ciphertext-only challenge (125 letters).
Read more...

Click here to get to the corresponding forum topic to share your opinion.
Click here to download the challenge.
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Author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published on: 2014-12-24 00:33
Maximum number of attempts for this challenge: 15

All successful users of this challenge

Rank User (#57) Achieved points (Global score) y-m-d - h:m:s

Bart den Hartog (Bart13) 2000 (148936) 2014-12-24 09:59:48
Kurt Gebauer (Yokozuna) 1725 (282608) 2014-12-26 03:32:17
Armin Krauss (argh) 1725 (206965) 2014-12-26 21:24:22
Michael Möller (michaelm) 1660 (253196) 2014-12-27 08:15:48
#5 Francisco Moraes (fmoraes) 1613 (90044) 2014-12-28 13:29:32
#6 George (Theofanidis) 1613 (123216) 2014-12-28 22:36:24
#7 Robert (rm) 1444 (56475) 2015-01-05 03:01:18
#8 E.T (Ertheb) 1406 (81809) 2015-01-09 16:57:01
#9 Alain (Integral) 1341 (207924) 2015-01-21 19:13:46
#10 Hans Joachim Girulat (joregi) 1286 (36278) 2015-02-11 09:29:25
#11 Claude Vaillancourt (Cl3v3r) 1283 (44129) 2015-02-13 03:09:20
#12 Nils (NiKo) 1273 (5155) 2015-02-19 16:31:30
#13 George Lasry (george4096) 1240 (399565) 2015-03-21 14:09:09
#14 Nils (NoelzzeN) 1217 (2546) 2015-04-25 13:12:41
#15 zahir mohsen moradi (ariobarzan) 1172 (99757) 2015-09-18 04:25:22
#16 Snake (snk) 1172 (187783) 2015-09-18 13:31:55
#17 Forrest Gump (Polyphem) 1159 (38763) 2015-12-07 18:00:24
#18 Szabó Zoltán (szabo.z87) 1153 (55604) 2016-02-02 21:18:14
#19 Julia Bernotat (El Greco ) 1150 (81129) 2016-02-27 01:33:49
#20 The Killer (Killer) 1150 (42393) 2016-02-29 01:41:53
#21 Martin (martinbucher) 1146 (38365) 2016-04-12 23:43:43
#22 Rainer Zufall (kiekuk) 1138 (56786) 2016-07-18 11:04:16
#23 Norbert Biermann (Norbert) 1137 (47790) 2016-07-31 15:53:39
#24 chris_3stones (3stones) 1133 (38845) 2016-10-10 20:35:59
#25 Alain Collignon (vexilla72) 1133 (123666) 2016-10-16 07:29:56
#26 J-L Morel (Rossignol) 1128 (42130) 2017-01-20 09:22:01
#27 Nicolas (nicosPavlov) 1127 (257791) 2017-02-07 02:37:23
#28 chris (c2) 1125 (51973) 2017-03-13 21:23:43
#29 Mir Dim (mir0soft) 1125 (79760) 2017-03-17 07:37:36
#30 Nils Rehwald (NoelzeN) 1125 (3465) 2017-03-22 12:32:32
#31 D3d4lu5 (D3d4lu5) 1119 (363488) 2017-08-12 05:24:12
#32 Lane Williams (planetlane) 1115 (34637) 2018-01-08 18:38:16
#33 Danny Higgins (hamster147) 1113 (39638) 2018-03-22 19:37:56
#34 Ignacio (Moebiusar) 1113 (7390) 2018-03-23 15:14:50
#35 Eric (ExAstris) 1111 (54941) 2018-06-19 01:35:01
#36 Random Dude (rnd) 1108 (103645) 2018-09-24 23:45:16
#37 João Vaz Martins (Awakening Star)