| The Syllabary Cipher – Part 2 | 1,341 | Nov. 25, 2022, 2:06 p.m. |
| The Syllabary Cipher – Part 1 | 105 | Nov. 17, 2022, 5:16 p.m. |
| ORYX Stream Cipher — Part 4a | 1,088 | March 4, 2022, 1:52 p.m. |
| ORYX Stream Cipher — Part 3 (revised) | 1,086 | Feb. 19, 2022, 11:06 p.m. |
| M-138 — Part 4 | 1,091 | Feb. 18, 2022, 11:04 p.m. |
| Pigpen with a twist — Part 3 | 1,082 | Feb. 15, 2022, 9:22 a.m. |
| Pigpen with a twist — Part 2 | 1,082 | Feb. 14, 2022, 6:55 p.m. |
| Not-so-Secret Message from Malawi — Part II (ECC) | 1,080 | Feb. 12, 2022, 10:42 p.m. |
| The Last Note | 100 | Feb. 11, 2022, 10:06 p.m. |
| Recycled One-Time Pad | 100 | Feb. 11, 2022, 9:46 p.m. |
| Playfair with hints about the grid | 100 | Feb. 11, 2022, 8:14 p.m. |
| A hidden word — Part 2 | 100 | Feb. 11, 2022, 9:08 a.m. |
| Playfair Encryption | 100 | Feb. 11, 2022, 7:43 a.m. |
| Enigma Combinatorics | 100 | Feb. 8, 2022, 9:54 p.m. |
| Enigma Messages with Repeated Letters — Part 5 | 100 | Feb. 8, 2022, 9:20 p.m. |
| Enigma Messages with Repeated Letters — Part 4 | 100 | Feb. 8, 2022, 9:19 p.m. |
| Enigma Messages with Repeated Letters — Part 2 | 100 | Feb. 6, 2022, 11:54 p.m. |
| Enigma Messages with Repeated Letters — Part 3 | 100 | Feb. 5, 2022, 10:56 a.m. |
| Enigma Messages | 100 | Feb. 4, 2022, 9:14 p.m. |
| Enigma Messages with Repeated Letters — Part 1 | 100 | Feb. 3, 2022, 9:47 p.m. |
| Classical Ciphers^3 | 100 | Feb. 3, 2022, 12:19 a.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | Feb. 1, 2022, 10:52 p.m. |
| Number Sequence — Part 6 | 100 | Jan. 30, 2022, 3:03 p.m. |
| Modular Sequences | 100 | Jan. 29, 2022, 10:54 p.m. |
| Find the right route — Part 3 | 100 | Jan. 29, 2022, 2:05 p.m. |
| Find the right route — Part 2 | 100 | Jan. 29, 2022, 11:26 a.m. |
| Find the right route — Part 1 | 100 | Jan. 29, 2022, 9:36 a.m. |
| Reserve Hand Procedure — Part 1 | 100 | Jan. 27, 2022, 10:56 p.m. |
| Polyphonic Substitution Cipher — Part 2 | 1,128 | Jan. 26, 2022, 11:37 p.m. |
| Polyphonic Substitution Cipher — Part 1 | 1,126 | Jan. 26, 2022, 11:05 p.m. |
| Fastest in the West | 1,109 | Jan. 25, 2022, 5:04 p.m. |
| Spanish Strip Cipher — Part 2 | 1,088 | Jan. 24, 2022, 11:40 p.m. |
| Spanish Strip Cipher — Part 1 | 1,088 | Jan. 24, 2022, 9:50 p.m. |
| Advent Challenge — Part 4 | 1,106 | Jan. 24, 2022, 8:51 a.m. |
| Advent Challenge — Part 3 | 1,106 | Jan. 23, 2022, 8:10 p.m. |
| Advent-Challenge — Part 2 | 1,106 | Jan. 23, 2022, 7:39 p.m. |
| Double Column Transposition — Part 4 | 1,089 | Jan. 23, 2022, 12:38 p.m. |
| Trendy Messenger | 1,109 | Jan. 19, 2022, 10:20 p.m. |
| Polyhomophonic Substitution — Part 2 | 1,133 | Jan. 18, 2022, 11:03 p.m. |
| Lattice Part 1 | 1,081 | Jan. 16, 2022, 7:25 p.m. |
| Polyhomophonic Substitution — Part 1 | 100 | Jan. 13, 2022, 11:36 p.m. |
| Wheatstone Cryptograph — Part 2 | 1,178 | Jan. 13, 2022, 2:12 p.m. |
| Wheatstone Cryptograph — Part 1 | 100 | Jan. 8, 2022, 1:38 a.m. |
| Pigpen with a twist — Part 1 | 100 | June 26, 2021, 5:19 p.m. |
| Kaskade-S/T — Part 3 | 1,083 | Feb. 26, 2021, 7:15 a.m. |
| Kaskade-S/T — Part 2 | 1,083 | Feb. 22, 2021, 2:55 p.m. |
| Kaskade-S/T — Part 1 | 100 | Feb. 20, 2021, 6:19 p.m. |
| AES key — encoded in the machine readable zone of a European ePassport | 1,085 | Feb. 20, 2021, 12:59 p.m. |
| Zodiac Cipher | 100 | Feb. 18, 2021, 11:50 p.m. |
| CMEA 1 | 1,082 | Feb. 18, 2021, 6:32 p.m. |
| BCR code (Book-Caesar-RSA) | 1,087 | Feb. 15, 2021, 11:39 p.m. |
| RSA Factoring Challenge: RSA-232 | 0 | Feb. 15, 2021, 8:33 p.m. |
| RSA Factoring Challenge: RSA-250 | 0 | Feb. 15, 2021, 8:32 p.m. |
| RSA Factoring Challenge: RSA-240 | 0 | Feb. 15, 2021, 8:30 p.m. |
| Unconcealed RSA messages | 1,084 | Feb. 15, 2021, 7:19 p.m. |
| Smartcard RSA | 1,082 | Feb. 14, 2021, 5:52 p.m. |
| RSA Factoring Challenge: RSA-230 | 0 | Feb. 11, 2021, 10:53 p.m. |
| RSA Factoring Challenge: RSA-220 | 0 | Feb. 11, 2021, 10:52 p.m. |
| RSA Factoring Challenge: RSA-210 | 0 | Feb. 11, 2021, 10:50 p.m. |
| RSA Factoring Challenge: RSA-704 | 0 | Feb. 11, 2021, 10:48 p.m. |
| Partial Key Exposure with RSA — Part 1 | 1,085 | Feb. 10, 2021, 10:52 p.m. |
| Enigma Part 2 | 1,082 | Feb. 9, 2021, 10:12 p.m. |
| Enigma Part 1 | 1,082 | Feb. 8, 2021, 10:04 p.m. |
| Lightweight Introduction to Lattices — Part 3 | 1,186 | Feb. 7, 2021, 11:05 p.m. |
| Lightweight Introduction to Lattices — Part 2 | 100 | Feb. 7, 2021, 10:23 p.m. |
| Lightweight Introduction to Lattices — Part 1 | 100 | Feb. 7, 2021, 8:07 p.m. |
| Double Column Transposition — Part 3 | 1,096 | March 5, 2020, 11:54 p.m. |
| Double Column Transposition — Part 2 | 1,096 | March 5, 2020, 11:36 p.m. |
| Double Column Transposition — Part 1 | 1,096 | March 5, 2020, 7:19 a.m. |
| ORYX Stream Cipher Part II | 1,084 | Feb. 22, 2020, 9:25 a.m. |
| ORYX Stream Cipher Part I | 1,084 | Feb. 22, 2020, 8:24 a.m. |
| Hybrid Encryption I | 1,084 | Feb. 16, 2020, 10:01 p.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,084 | Feb. 16, 2020, 5:58 p.m. |
| Lunchtime Attack on the Fully Homomorphic Encryption Scheme | 1,086 | Oct. 13, 2019, 10:29 a.m. |
| A really long number sequence | 1,088 | Oct. 12, 2019, 9:24 p.m. |
| Monoalphabetic Substitution with Camouflage — Part 5 | 1,090 | July 29, 2019, 9:43 p.m. |
| Monoalphabetic substitution with camouflage — Part 4 | 100 | July 29, 2019, 9:23 p.m. |
| Monoalphabetic substitution with camouflage — Part 3 | 1,089 | July 29, 2019, 7:10 p.m. |
| Monoalphabetic substitution with camouflage — Part 2 | 1,089 | July 28, 2019, 11:13 p.m. |
| Monoalphabetic substitution with camouflage — Part 1 | 100 | July 28, 2019, 8:28 a.m. |
| Homophonic Encryption — Part 2 | 1,246 | July 27, 2019, 11:58 p.m. |
| Homophonic Encryption — Part 4 | 1,246 | July 27, 2019, 10:50 p.m. |
| Homophonic Encryption — Part 3 | 1,246 | July 27, 2019, 10:34 p.m. |
| Homophonic Encryption — Part 1 | 1,243 | July 27, 2019, 8:56 p.m. |
| M-138 — Part 3 | 1,102 | July 27, 2019, 12:45 p.m. |
| Unusual encryption using a diophantine equation | 1,088 | July 24, 2019, 10:41 p.m. |
| Molehunt (Part 3/3) | 1,086 | July 23, 2019, 8:56 p.m. |
| Number Sequence — Part 7 | 100 | July 21, 2019, 10:16 a.m. |
| Number Sequence — Part 9 | 100 | July 21, 2019, 10:03 a.m. |
| Molehunt (Part 2/3) | 100 | July 20, 2019, 10:43 p.m. |
| Molehunt (Part 1/3) | 100 | July 20, 2019, 5:16 p.m. |
| M-138 — Part 2 | 1,103 | July 16, 2019, 2:28 p.m. |
| M-138 — Part 1 | 100 | July 16, 2019, 12:17 p.m. |
| RSA: Two different keys — same ciphertext | 1,088 | July 16, 2019, 9:02 a.m. |
| The Einstein Enigma | 1,142 | July 16, 2019, 7:43 a.m. |
| Factorization Cipher — Part 3 | 1,089 | July 15, 2019, 10:42 p.m. |
| Factorization Cipher — Part 2 | 1,089 | July 15, 2019, 7:49 p.m. |
| Number Sequence — Part 5 | 100 | July 14, 2019, 9:46 p.m. |
| Summer Job | 1,153 | July 14, 2019, 5:26 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,086 | July 13, 2019, 9:27 a.m. |
| Nils away on travel | 100 | July 12, 2019, 10:55 p.m. |
| Broadcasting and low exponent — RSA Attack | 1,088 | July 12, 2019, 9 p.m. |
| Alice's Birthday Party (Part 2) | 1,086 | July 12, 2019, 8:48 p.m. |
| Alice's Birthday Party (Part 1) | 1,086 | July 12, 2019, 5:36 p.m. |
| ¿No Hablas Español? No problemo! | 100 | July 12, 2019, 12:05 a.m. |
| From Russia with Love | 100 | July 11, 2019, 10:17 p.m. |
| Modified Caesar Cipher | 100 | July 11, 2019, 9:53 p.m. |
| Snow White and the seven dwarfs | 100 | July 11, 2019, 6:49 p.m. |
| Advent-Challenge — Part 1 | 100 | July 11, 2019, 6:06 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | July 11, 2019, 5:59 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | July 11, 2019, 5:17 p.m. |
| Number Sequence — Part 3 | 100 | July 11, 2019, 4:19 p.m. |
| Number Sequence — Part 8 | 100 | July 10, 2019, 10:54 p.m. |
| How do you become a big cryptographer? | 100 | July 10, 2019, 10:36 p.m. |
| Number Sequence — Part 10 | 100 | July 10, 2019, 10:07 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | July 8, 2019, 11:53 p.m. |
| One-Time Pad with Flaws | 100 | July 8, 2019, 11:27 p.m. |
| Number Sequence — Part 4 | 100 | July 8, 2019, 10:55 p.m. |
| Grille Cipher | 100 | July 8, 2019, 5:07 p.m. |
| Cracking SHA1-Hashed Passwords | 1,087 | July 7, 2019, 9:15 p.m. |
| Factorization Cipher — Part 1 | 100 | July 7, 2019, 9:11 p.m. |
| Monoalphabetic Substitution | 100 | July 7, 2019, 8:41 p.m. |
| Letter to the Templars — Part 3 | 1,092 | July 7, 2019, 5:43 p.m. |
| Letter to the Templars — Part 2 | 100 | July 7, 2019, 4:55 p.m. |
| Letter to the Templars — Part 1 | 100 | July 7, 2019, 10:48 a.m. |
| Beaver Code | 100 | July 7, 2019, 10:08 a.m. |
| A hidden word | 100 | July 7, 2019, 9:51 a.m. |
| Number Sequence — Part 2 | 100 | July 7, 2019, 9:19 a.m. |
| Number Sequence | 100 | July 7, 2019, 8:18 a.m. |
| Original Caesar Cipher | 100 | July 6, 2019, 11:02 p.m. |
| Caesar Encryption | 100 | July 6, 2019, 11 p.m. |
| Autokey Cipher | 100 | July 6, 2019, 10:40 p.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 101 | July 6, 2019, 10:08 p.m. |
Gold0
Silver0
Bronze0
