| General | CERTainly not | 30 | |
| Crypto on the Web | Token Appreciation | 5 | |
| Diffie-Hellman | Working with Fields | 10 | |
| RSA | Factoring | 15 | |
| RSA | RSA Signatures | 25 | |
| RSA | RSA Decryption | 20 | |
| RSA | Private Keys | 20 | |
| Elliptic Curves | Background Reading | 5 | |
| RSA | Euler's Totient | 20 | |
| RSA | Public Keys | 15 | |
| RSA | Modular Exponentiation | 10 | |
| Symmetric Ciphers | Resisting Bruteforce | 10 | |
| Symmetric Ciphers | Keyed Permutations | 5 | |
| Lattices | What's a Lattice? | 40 | |
| Lattices | Size and Basis | 15 | |
| Lattices | Vectors | 10 | |
| Mathematics | Chinese Remainder Theorem | 40 | |
| Mathematics | Quadratic Residues | 25 | |
| General | Privacy-Enhanced Mail? | 25 | |
| General | Lemur XOR | 40 | |
| General | You either know, XOR you don't | 30 | |
| General | Favourite byte | 20 | |
| General | Encoding Challenge | 40 | |
| General | Bytes and Big Integers | 10 | |
| General | Modular Inverting | 25 | |
| General | Modular Arithmetic 2 | 20 | |
| General | Modular Arithmetic 1 | 20 | |
| General | Extended GCD | 20 | |
| General | Greatest Common Divisor | 15 | |
| General | XOR Properties | 15 | |
| General | XOR Starter | 10 | |
| General | Base64 | 10 | |
| General | Hex | 5 | |
| General | ASCII | 5 | |
| Introduction | Network Attacks | 5 | |
| Introduction | Great Snakes | 3 | |
| Introduction | Finding Flags | 2 |
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