| Weakened Granit — Part 1 | 100 | April 1, 2023, 6:16 p.m. |
| Monoalphabetic Substitution with Camouflage — Part 5 | 1,081 | March 31, 2023, 4:59 p.m. |
| Monoalphabetic substitution with camouflage — Part 4 | 100 | March 31, 2023, 4:42 p.m. |
| Monoalphabetic substitution with camouflage — Part 3 | 1,080 | March 31, 2023, 1:12 p.m. |
| Monoalphabetic substitution with camouflage — Part 1 | 100 | March 31, 2023, 11:51 a.m. |
| Polyhomophonic Substitution — Part 1 | 100 | March 30, 2023, 8:23 p.m. |
| Music Code — Part 1 | 100 | March 30, 2023, 5:28 p.m. |
| The Josse Challenge – Part 2 | 1,327 | March 29, 2023, 5:57 p.m. |
| The Josse Challenge – Part 1 | 1,290 | March 29, 2023, 2:03 p.m. |
| Music Code — Part 2 | 1,079 | March 28, 2023, 5:23 p.m. |
| Number Sequence — Part 5 | 100 | March 28, 2023, 3:40 p.m. |
| An Invisible Message | 100 | March 28, 2023, 2:18 p.m. |
| AES ECB Wrong Encoding | 1,099 | March 28, 2023, 1:48 p.m. |
| CMEA 2 | 13,006 | March 27, 2023, 12:33 p.m. |
| Playfair Encryption | 100 | March 27, 2023, 11:46 a.m. |
| Molehunt (Part 3/3) | 1,078 | March 26, 2023, 2:37 p.m. |
| Cascading Encryption — Part 1/3 | 100 | March 24, 2023, 7:40 p.m. |
| Hill Cipher with Sudoku Key | 100 | March 24, 2023, 9:31 a.m. |
| Unusual encryption using a diophantine equation | 1,080 | March 23, 2023, 10:23 a.m. |
| Typex — Part 2 | 1,083 | March 22, 2023, 7:48 p.m. |
| Smartcard RSA | 1,078 | March 22, 2023, 11:36 a.m. |
| Merkle-Hellman Knapsack Challenge — Part 2 | 1,201 | March 21, 2023, 6:21 p.m. |
| Typex — Part 1 | 1,083 | March 20, 2023, 7:25 p.m. |
| ADFGVX — Part 2 | 100 | March 20, 2023, 7:22 p.m. |
| ADFGVX — Part 1 | 100 | March 20, 2023, 6:11 p.m. |
| Unconcealed RSA messages | 1,080 | March 20, 2023, 3:55 p.m. |
| Playfair with hints about the grid | 100 | March 20, 2023, 12:24 p.m. |
| Monoalphabetic Substitution with Nostradamus Flavor | 1,106 | March 20, 2023, noon |
| The Last Note | 100 | March 20, 2023, 8:44 a.m. |
| Multilingual Monoalphabetic Substitution | 100 | March 19, 2023, 8:25 p.m. |
| Partial Key Exposure with RSA — Part 1 | 1,081 | March 19, 2023, 9:51 a.m. |
| CMEA 1 | 1,078 | March 18, 2023, 6:15 p.m. |
| Turing Bombe Enigma I | 100 | March 14, 2023, 10:58 a.m. |
| Trifid Cipher | 100 | March 12, 2023, 5:55 p.m. |
| Enigma Part 2 | 1,078 | March 12, 2023, 4:27 p.m. |
| The Book Code: A Challenge for Bookworms | 100 | March 11, 2023, 9:47 p.m. |
| Enigma Messages | 100 | March 11, 2023, 6:58 p.m. |
| Enigma Part 1 | 1,078 | March 11, 2023, 6:34 p.m. |
| Enigma Combinatorics | 100 | March 10, 2023, 10:25 p.m. |
| Molehunt (Part 2/3) | 100 | March 10, 2023, 9:31 a.m. |
| Molehunt (Part 1/3) | 100 | March 9, 2023, 7:51 p.m. |
| Factorization Cipher — Part 3 | 1,080 | March 9, 2023, 6:59 p.m. |
| BCR code (Book-Caesar-RSA) | 1,082 | March 8, 2023, 7:47 p.m. |
| Enigma Messages with Repeated Letters — Part 5 | 100 | March 7, 2023, 2:13 p.m. |
| Enigma Messages with Repeated Letters — Part 4 | 100 | March 7, 2023, 2:11 p.m. |
| Enigma Messages with Repeated Letters — Part 3 | 100 | March 7, 2023, 1:36 p.m. |
| Enigma Messages with Repeated Letters — Part 2 | 100 | March 7, 2023, 1:23 p.m. |
| Cracking SHA1-Hashed Passwords | 1,079 | March 7, 2023, 9:36 a.m. |
| Enigma Messages with Repeated Letters — Part 1 | 100 | March 6, 2023, 2:18 p.m. |
| Cryptanalysis Hacking Puzzles — Part 1 | 100 | March 5, 2023, 4:22 p.m. |
| The LoRa Cipher: Logic Randomness — Part 1 | 1,115 | March 5, 2023, 2:50 p.m. |
| Lightweight Introduction to Lattices — Part 3 | 1,119 | March 5, 2023, 1:50 p.m. |
| Advent Challenge — Part 4 | 1,099 | March 4, 2023, 8:15 p.m. |
| Advent Challenge — Part 3 | 1,099 | March 4, 2023, 6:44 p.m. |
| Advent-Challenge — Part 2 | 1,099 | March 4, 2023, 6:26 p.m. |
| Find the right route — Part 1 | 100 | March 4, 2023, 2:58 p.m. |
| Modular Sequences | 100 | March 4, 2023, 2:19 p.m. |
| A really long number sequence | 1,080 | March 4, 2023, 11:41 a.m. |
| Pigpen with a twist — Part 1 | 100 | March 3, 2023, 6:24 p.m. |
| Nils away on travel | 100 | March 3, 2023, 4:32 p.m. |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 1 | 100 | March 2, 2023, 9:24 a.m. |
| Summer Job | 1,102 | March 1, 2023, 9:39 p.m. |
| Hybrid Encryption I | 1,078 | March 1, 2023, 8:39 p.m. |
| Fastest in the West | 1,102 | March 1, 2023, 8:12 p.m. |
| ECDH-Key Exchange for Beginners | 100 | March 1, 2023, 6:39 p.m. |
| Factorization Cipher — Part 2 | 1,080 | Feb. 23, 2023, 5:34 p.m. |
| ¿No Hablas Español? No problemo! | 100 | Feb. 23, 2023, 4:17 p.m. |
| RSA Factoring Challenge: RSA-210 | 0 | Feb. 23, 2023, 3:16 p.m. |
| RSA Factoring Challenge: RSA-220 | 0 | Feb. 23, 2023, 3:15 p.m. |
| RSA Factoring Challenge: RSA-230 | 0 | Feb. 23, 2023, 3:15 p.m. |
| RSA Factoring Challenge: RSA-232 | 0 | Feb. 23, 2023, 3:13 p.m. |
| RSA Factoring Challenge: RSA-240 | 0 | Feb. 23, 2023, 3:12 p.m. |
| RSA Factoring Challenge: RSA-250 | 0 | Feb. 23, 2023, 3:11 p.m. |
| RSA Factoring Challenge: RSA-704 | 0 | Feb. 23, 2023, 3:10 p.m. |
| AES key — encoded in the machine readable zone of a European ePassport | 1,081 | Feb. 23, 2023, 2:48 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,078 | Feb. 23, 2023, 12:42 p.m. |
| Alice's Birthday Party (Part 2) | 1,078 | Feb. 23, 2023, 11:33 a.m. |
| Alice's Birthday Party (Part 1) | 1,078 | Feb. 23, 2023, 10:53 a.m. |
| The Syllabary Cipher – Part 1 | 101 | Feb. 23, 2023, 10:03 a.m. |
| RSA: Two different keys — same ciphertext | 1,080 | Feb. 22, 2023, 2:44 p.m. |
| Broadcasting and low exponent — RSA Attack | 1,080 | Feb. 22, 2023, 2:05 p.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,078 | Feb. 22, 2023, 10:03 a.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | Feb. 18, 2023, 6:17 p.m. |
| News from Castle Mansfeld | 100 | Feb. 18, 2023, 5:41 p.m. |
| Classical Ciphers^3 | 100 | Feb. 17, 2023, 5:34 p.m. |
| Reserve Hand Procedure — Part 1 | 100 | Feb. 17, 2023, 2:55 p.m. |
| Modified Caesar Cipher | 100 | Feb. 17, 2023, 2:09 p.m. |
| One-Time Pad with Flaws | 100 | Feb. 17, 2023, 12:23 p.m. |
| Factorization Cipher — Part 1 | 100 | Feb. 17, 2023, 11:31 a.m. |
| A hidden word | 100 | Feb. 17, 2023, 10:45 a.m. |
| How do you become a big cryptographer? | 100 | Feb. 17, 2023, 10:40 a.m. |
| Kaskade-S/T — Part 2 | 1,079 | Feb. 16, 2023, 6:54 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | Feb. 16, 2023, 11:19 a.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | Feb. 16, 2023, 11:02 a.m. |
| Kaskade-S/T — Part 1 | 100 | Feb. 15, 2023, 4:39 p.m. |
| Strange Message from Thessaloniki | 100 | Feb. 14, 2023, 1:51 p.m. |
| Snow White and the seven dwarfs | 100 | Feb. 13, 2023, 3:18 p.m. |
| M-138 — Part 1 | 100 | Feb. 8, 2023, 12:19 p.m. |
| Autokey Cipher | 100 | Feb. 7, 2023, 2:39 p.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 100 | Feb. 7, 2023, 1:40 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | Feb. 7, 2023, 12:11 p.m. |
| Wheatstone Cryptograph — Part 1 | 100 | Feb. 7, 2023, 11:40 a.m. |
| Number Sequence — Part 7 | 100 | Feb. 7, 2023, 8:26 a.m. |
| Alberti Challenge — Part 1 | 100 | Feb. 6, 2023, 5:43 p.m. |
| Number Sequence — Part 4 | 100 | Feb. 6, 2023, 3:13 p.m. |
| Number Sequence — Part 6 | 100 | Feb. 6, 2023, 2:27 p.m. |
| Number Sequence — Part 8 | 100 | Feb. 6, 2023, 2:14 p.m. |
| Number Sequence — Part 9 | 100 | Feb. 6, 2023, 2:11 p.m. |
| Number Sequence — Part 3 | 100 | Feb. 6, 2023, 2:06 p.m. |
| Number Sequence — Part 10 | 100 | Feb. 2, 2023, 6:53 p.m. |
| Merkle-Hellman Knapsack Challenge - Part 1 | 101 | Feb. 2, 2023, 4:53 p.m. |
| Caesar Encryption | 100 | Feb. 2, 2023, 2:12 p.m. |
| The Einstein Enigma | 1,100 | Feb. 2, 2023, 2:04 p.m. |
| Letter to the Templars — Part 3 | 1,083 | Nov. 2, 2022, 5:58 p.m. |
| Letter to the Templars — Part 2 | 100 | Nov. 2, 2022, 5:49 p.m. |
| Letter to the Templars — Part 1 | 100 | Nov. 2, 2022, 5:41 p.m. |
| From Russia with Love | 100 | Nov. 2, 2022, 5:06 p.m. |
| Monoalphabetic Substitution | 100 | Nov. 2, 2022, 4:18 p.m. |
| Double Columnar Transposition | 100 | Nov. 2, 2022, 2:10 p.m. |
| Number Sequence | 100 | Oct. 30, 2022, 8:43 p.m. |
| Advent-Challenge — Part 1 | 100 | Oct. 30, 2022, 8:17 p.m. |
| Grille Cipher | 100 | Oct. 30, 2022, 6:23 p.m. |
| Number Sequence — Part 2 | 100 | Oct. 30, 2022, 11:54 a.m. |
| Beaver Code | 100 | Oct. 30, 2022, 11:47 a.m. |
| Original Caesar Cipher | 100 | Oct. 30, 2022, 11:44 a.m. |
| A Secret Message from Castle Mansfeld | 100 | Oct. 30, 2022, 11:43 a.m. |
Gold0
Silver0
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