| BCR code (Book-Caesar-RSA) | 1,084 | May 25, 2022, 6:30 p.m. |
| Not-so-Secret Message from Malawi — Part II (ECC) | 1,080 | May 25, 2022, 4:54 p.m. |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 1 | 100 | May 24, 2022, 6:55 p.m. |
| ECDH-Key Exchange for Beginners | 100 | May 20, 2022, 6:58 p.m. |
| A really long number sequence | 1,081 | May 17, 2022, 7:35 p.m. |
| Summer Job | 1,107 | May 16, 2022, 5:07 a.m. |
| Reserve Hand Procedure — Part 1 | 100 | May 15, 2022, 5:39 a.m. |
| Modified Caesar Cipher | 100 | May 15, 2022, 4:23 a.m. |
| Polyhomophonic Substitution — Part 1 | 100 | May 14, 2022, 10:51 p.m. |
| M-138 — Part 3 | 1,090 | May 14, 2022, 9:45 p.m. |
| Enigma Part 2 | 1,080 | May 14, 2022, 9:26 p.m. |
| Enigma Messages with Repeated Letters — Part 5 | 100 | May 14, 2022, 8:36 p.m. |
| Enigma Messages with Repeated Letters — Part 4 | 100 | May 14, 2022, 8:28 p.m. |
| Enigma Messages with Repeated Letters — Part 3 | 100 | May 14, 2022, 8:26 p.m. |
| Enigma Messages with Repeated Letters — Part 2 | 100 | May 14, 2022, 8:17 p.m. |
| Enigma Messages with Repeated Letters — Part 1 | 100 | May 14, 2022, 7:51 p.m. |
| Factorization Cipher — Part 3 | 1,082 | May 14, 2022, 4:42 a.m. |
| Playfair Encryption | 100 | May 13, 2022, 9:13 p.m. |
| Trifid Cipher | 100 | May 13, 2022, 8:37 p.m. |
| M-138 — Part 2 | 1,090 | May 13, 2022, 5:53 p.m. |
| M-138 — Part 1 | 100 | May 13, 2022, 5:14 p.m. |
| Unusual encryption using a diophantine equation | 1,081 | May 12, 2022, 10:53 p.m. |
| Image Noise | 100 | May 12, 2022, 7:09 p.m. |
| The Book Code: A Challenge for Bookworms | 100 | May 12, 2022, 6:47 p.m. |
| Pigpen with a twist — Part 1 | 100 | May 12, 2022, 6:28 p.m. |
| ¿No Hablas Español? No problemo! | 100 | May 12, 2022, 5:38 p.m. |
| Hybrid Encryption I | 1,080 | May 12, 2022, 5:10 p.m. |
| How do you become a big cryptographer? | 100 | May 12, 2022, 5:45 a.m. |
| Snow White and the seven dwarfs | 100 | May 12, 2022, 4:52 a.m. |
| One-Time Pad with Flaws | 100 | May 12, 2022, 4:40 a.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | May 12, 2022, 3:38 a.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | May 12, 2022, 2:16 a.m. |
| Grille Cipher | 100 | May 12, 2022, 1:54 a.m. |
| Cracking SHA1-Hashed Passwords | 1,081 | May 12, 2022, 1:32 a.m. |
| Monoalphabetic Substitution | 100 | May 12, 2022, 12:33 a.m. |
| Number Sequence — Part 7 | 100 | May 11, 2022, 10:19 p.m. |
| RSA Factoring Challenge: RSA-704 | 0 | May 11, 2022, 8:29 p.m. |
| RSA Factoring Challenge: RSA-210 | 0 | May 11, 2022, 8:28 p.m. |
| RSA Factoring Challenge: RSA-220 | 0 | May 11, 2022, 8:28 p.m. |
| RSA Factoring Challenge: RSA-230 | 0 | May 11, 2022, 8:27 p.m. |
| Partial Key Exposure with RSA — Part 1 | 1,082 | May 11, 2022, 8:26 p.m. |
| AES ECB Wrong Encoding | 1,104 | May 11, 2022, 5:28 p.m. |
| Monoalphabetic Substitution with Nostradamus Flavor | 1,113 | May 11, 2022, 4:17 p.m. |
| Find the right route — Part 1 | 100 | May 11, 2022, 6:06 a.m. |
| RSA: Two different keys — same ciphertext | 1,081 | May 11, 2022, 5:24 a.m. |
| Smartcard RSA | 1,080 | May 11, 2022, 5:06 a.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,080 | May 11, 2022, 4:26 a.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,080 | May 11, 2022, 3:06 a.m. |
| Lightweight Introduction to Lattices — Part 3 | 1,133 | May 11, 2022, 1:37 a.m. |
| Factorization Cipher — Part 2 | 1,082 | May 10, 2022, 10:37 p.m. |
| Alice's Birthday Party (Part 2) | 1,080 | May 10, 2022, 9:14 p.m. |
| Alice's Birthday Party (Part 1) | 1,080 | May 10, 2022, 9:07 p.m. |
| Letter to the Templars — Part 3 | 1,084 | May 10, 2022, 9 p.m. |
| Broadcasting and low exponent — RSA Attack | 1,081 | May 10, 2022, 8:22 p.m. |
| From Russia with Love | 100 | May 10, 2022, 4:45 p.m. |
| Playfair with hints about the grid | 100 | May 9, 2022, 7:48 p.m. |
| Number Sequence — Part 6 | 100 | May 9, 2022, 7:42 p.m. |
| A hidden word — Part 2 | 100 | May 9, 2022, 7:40 p.m. |
| Number Sequence — Part 8 | 100 | May 9, 2022, 7:28 p.m. |
| Wheatstone Cryptograph — Part 1 | 100 | May 9, 2022, 7:25 p.m. |
| Lightweight Introduction to Lattices — Part 2 | 100 | May 9, 2022, 4:48 a.m. |
| RSA Factoring Challenge: RSA-232 | 0 | May 8, 2022, 10:22 p.m. |
| RSA Factoring Challenge: RSA-240 | 0 | May 8, 2022, 10:22 p.m. |
| RSA Factoring Challenge: RSA-250 | 0 | May 8, 2022, 10:22 p.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 100 | May 8, 2022, 10:13 p.m. |
| Number Sequence — Part 9 | 100 | May 8, 2022, 10:11 p.m. |
| Advent-Challenge — Part 1 | 100 | May 8, 2022, 10:09 p.m. |
| Number Sequence — Part 10 | 100 | May 8, 2022, 10:07 p.m. |
| Modular Sequences | 100 | May 8, 2022, 9:48 p.m. |
| Autokey Cipher | 100 | May 8, 2022, 5:44 p.m. |
| Cryptanalysis Hacking Puzzles — Part 1 | 100 | May 8, 2022, 5:21 p.m. |
| Lightweight Introduction to Lattices — Part 1 | 100 | May 8, 2022, 4:27 p.m. |
| Alberti Challenge — Part 1 | 102 | May 8, 2022, 5:41 a.m. |
| Factorization Cipher — Part 1 | 100 | May 8, 2022, 1:50 a.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | May 8, 2022, 1:36 a.m. |
| Letter to the Templars — Part 2 | 100 | May 8, 2022, 1:33 a.m. |
| A hidden word | 100 | May 8, 2022, 1:30 a.m. |
| Number Sequence — Part 4 | 100 | May 7, 2022, 7:11 p.m. |
| Number Sequence — Part 3 | 100 | May 7, 2022, 7:07 p.m. |
| Letter to the Templars — Part 1 | 100 | May 7, 2022, 7:06 p.m. |
| Beaver Code | 100 | May 7, 2022, 7 p.m. |
| Caesar Encryption | 100 | May 7, 2022, 6:53 p.m. |
| Number Sequence — Part 2 | 100 | May 7, 2022, 6:11 p.m. |
| Original Caesar Cipher | 100 | May 7, 2022, 6:10 p.m. |
| Number Sequence | 100 | May 7, 2022, 6:05 p.m. |
Gold0
Silver0
Bronze0
