| Mathematics | Chinese Remainder Theorem | 40 | |
| Mathematics | Modular Square Root | 35 | |
| Mathematics | Legendre Symbol | 35 | |
| Mathematics | Quadratic Residues | 25 | |
| General | Modular Inverting | 25 | |
| General | Modular Arithmetic 2 | 20 | |
| Hash Functions | MD0 | 80 | |
| Hash Functions | PriMeD5 | 100 | |
| Hash Functions | Hash Stuffing | 50 | |
| Hash Functions | Collider | 50 | |
| Hash Functions | Jack's Birthday Confusion | 30 | |
| Hash Functions | Jack's Birthday Hash | 20 | |
| Crypto on the Web | Authenticated Handshake | 40 | |
| Crypto on the Web | Decrypting TLS 1.3 | 35 | |
| Crypto on the Web | Decrypting TLS 1.2 | 30 | |
| Crypto on the Web | Saying Hello | 20 | |
| Crypto on the Web | TLS Handshake | 15 | |
| Crypto on the Web | Sharks on the Wire | 10 | |
| Crypto on the Web | Secure Protocols | 5 | |
| Crypto on the Web | JSON in JSON | 40 | |
| Crypto on the Web | RSA or HMAC? | 35 | |
| Crypto on the Web | JWT Secrets | 25 | |
| Crypto on the Web | No Way JOSE | 20 | |
| Crypto on the Web | JWT Sessions | 10 | |
| Crypto on the Web | Token Appreciation | 5 | |
| Symmetric Ciphers | Oh SNAP | 120 | |
| Symmetric Ciphers | Dancing Queen | 120 | |
| Symmetric Ciphers | Logon Zero | 80 | |
| Symmetric Ciphers | CTRIME | 70 | |
| Symmetric Ciphers | Bean Counter | 60 | |
| Symmetric Ciphers | Symmetry | 50 | |
| Symmetric Ciphers | Triple DES | 60 | |
| Symmetric Ciphers | Lazy CBC | 60 | |
| Symmetric Ciphers | Flipping Cookie | 60 | |
| Symmetric Ciphers | ECB CBC WTF | 55 | |
| General | Modular Arithmetic 1 | 20 | |
| General | Extended GCD | 20 | |
| General | Greatest Common Divisor | 15 | |
| General | You either know, XOR you don't | 30 | |
| General | XOR Properties | 15 | |
| General | Favourite byte | 20 | |
| General | XOR Starter | 10 | |
| General | Bytes and Big Integers | 10 | |
| General | Base64 | 10 | |
| General | Hex | 5 | |
| General | ASCII | 5 | |
| Introduction | Network Attacks | 5 | |
| Introduction | Finding Flags | 2 | |
| Introduction | Great Snakes | 3 |
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