| A Secret Message from Castle Mansfeld | 100 | Jan. 17, 2017, 12:50 a.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,094 | Jan. 15, 2017, 9:43 p.m. |
| Factorization Cipher — Part 3 | 1,100 | Jan. 10, 2017, 8:47 p.m. |
| RSA: Two different keys — same ciphertext | 1,098 | Jan. 7, 2017, 9:24 p.m. |
| Broadcasting and low exponent — RSA Attack | 1,098 | Jan. 7, 2017, 7:23 p.m. |
| Alice's Birthday Party (Part 2) | 1,094 | Jan. 7, 2017, 7:02 p.m. |
| Alice's Birthday Party (Part 1) | 1,094 | Jan. 7, 2017, 3:25 p.m. |
| Double Columnar Transposition | 100 | Jan. 6, 2017, 2:38 p.m. |
| Hybrid Encryption I | 1,094 | Jan. 3, 2017, 5:07 p.m. |
| M-138 — Part 2 | 1,129 | Jan. 3, 2017, 9:39 a.m. |
| BCR code (Book-Caesar-RSA) | 1,104 | Jan. 2, 2017, 1:24 p.m. |
| Cracking SHA1-Hashed Passwords | 1,096 | Jan. 1, 2017, 6:37 p.m. |
| Enigma Messages with Repeated Letters — Part 1 | 100 | Dec. 30, 2016, 8:11 p.m. |
| Enigma Messages with Repeated Letters — Part 2 | 100 | Dec. 30, 2016, 8:10 p.m. |
| Enigma Messages with Repeated Letters — Part 5 | 100 | Dec. 30, 2016, 8:06 p.m. |
| Enigma Messages with Repeated Letters — Part 4 | 100 | Dec. 30, 2016, 8:03 p.m. |
| Enigma Messages with Repeated Letters — Part 3 | 100 | Dec. 30, 2016, 7:54 p.m. |
| ECDH-Key Exchange for Beginners | 100 | Dec. 30, 2016, 9:38 a.m. |
| Trifid Cipher | 100 | Dec. 29, 2016, 6:07 p.m. |
| Number Sequence — Part 8 | 100 | Dec. 28, 2016, 5:39 p.m. |
| M-138 — Part 1 | 100 | Dec. 25, 2016, 2:26 p.m. |
| The Last Note | 100 | Dec. 16, 2016, 11:36 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,112 | Feb. 19, 2014, 7:50 p.m. |
| A really long number sequence | 1,122 | Feb. 16, 2014, 10:27 p.m. |
| Enigma Part 1 | 1,112 | Feb. 16, 2014, 6:46 p.m. |
| Hill Cipher with Sudoku Key | 101 | Feb. 16, 2014, 1:28 p.m. |
| ¿No Hablas Español? No problemo! | 100 | Feb. 15, 2014, 8:54 p.m. |
| Enigma Messages | 100 | Feb. 15, 2014, 5:35 p.m. |
| Turing Bombe Enigma I | 100 | Feb. 15, 2014, 11:14 a.m. |
| Enigma Combinatorics | 100 | Feb. 13, 2014, 11:46 p.m. |
| The Book Code: A Challenge for Bookworms | 100 | Feb. 13, 2014, 10:40 p.m. |
| Molehunt (Part 2/3) | 100 | Feb. 10, 2014, 9:20 p.m. |
| ADFGVX — Part 1 | 100 | Feb. 9, 2014, 7:22 p.m. |
| ADFGVX — Part 2 | 100 | Feb. 9, 2014, 7:08 p.m. |
| How do you become a big cryptographer? | 100 | Feb. 8, 2014, 2:28 p.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | Feb. 8, 2014, 1:58 p.m. |
| From Russia with Love | 101 | Feb. 8, 2014, 10:12 a.m. |
| Multilingual Monoalphabetic Substitution | 100 | Feb. 7, 2014, 5:45 p.m. |
| Modified Caesar Cipher | 100 | Feb. 5, 2014, 11:09 p.m. |
| Nils away on travel | 101 | Feb. 5, 2014, 3:09 p.m. |
| Snow White and the seven dwarfs | 100 | Feb. 4, 2014, 10:33 p.m. |
| Monoalphabetic substitution with camouflage — Part 1 | 100 | Feb. 4, 2014, 9:46 p.m. |
| Cascading Encryption — Part 1/3 | 100 | Feb. 3, 2014, 9:56 p.m. |
| Pigpen with a twist — Part 1 | 100 | Feb. 2, 2014, 8:31 p.m. |
| One-Time Pad with Flaws | 100 | Feb. 2, 2014, 2:17 p.m. |
| Playfair with hints about the grid | 100 | Feb. 2, 2014, 1:14 a.m. |
| Playfair Encryption | 100 | Feb. 2, 2014, 1:08 a.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | Feb. 1, 2014, 11:15 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | Feb. 1, 2014, 10:47 p.m. |
| Molehunt (Part 1/3) | 100 | Feb. 1, 2014, 3:27 p.m. |
| Classical Ciphers^3 | 100 | Jan. 31, 2014, 5:28 p.m. |
| Monoalphabetic Substitution | 100 | Jan. 30, 2014, 7:56 p.m. |
| Letter to the Templars — Part 3 | 1,146 | Jan. 30, 2014, 7:35 p.m. |
| Factorization Cipher — Part 1 | 100 | Jan. 30, 2014, 5:40 p.m. |
| Zodiac Cipher | 100 | Jan. 30, 2014, 2:11 p.m. |
| Reserve Hand Procedure — Part 1 | 100 | Jan. 30, 2014, 12:29 p.m. |
| Grille Cipher | 100 | Jan. 29, 2014, 9:29 p.m. |
| A hidden word | 100 | Jan. 29, 2014, 8:48 p.m. |
| Letter to the Templars — Part 2 | 100 | Jan. 29, 2014, 8:16 p.m. |
| Letter to the Templars — Part 1 | 100 | Jan. 29, 2014, 7:04 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | Jan. 29, 2014, 4:59 p.m. |
| Number Sequence — Part 4 | 100 | Jan. 29, 2014, 12:58 p.m. |
| Number Sequence — Part 3 | 100 | Jan. 29, 2014, 12:48 p.m. |
| Beaver Code | 100 | Jan. 28, 2014, 11:55 p.m. |
| Caesar Encryption | 100 | Jan. 28, 2014, 11:22 p.m. |
| Number Sequence — Part 2 | 100 | Jan. 28, 2014, 10:28 p.m. |
| Number Sequence | 100 | Jan. 28, 2014, 10:24 p.m. |
| Original Caesar Cipher | 100 | Jan. 28, 2014, 10:17 p.m. |
Gold0
Silver0
Bronze0
