SKILL.md

ctf-crypto

Provides cryptography attack techniques for CTF challenges. Use when attacking encryption, hashing, signatures, ZKP, PRNG, or mathematical crypto problems involving RSA, AES, ECC, lattices, LWE, CVP, number theory, Coppersmith, Pollard, Wiener, padding oracle, GCM, key derivation, or stream/block cipher weaknesses.

install ctf-crypto

# install the ctf-skills pack with the skills CLI

npx skills add ljagiello/ctf-skills

# or add only this skill to Claude Code: copy the folder

ctf-crypto/

# into

~/.claude/skills/ctf-crypto/ (all projects)

.claude/skills/ctf-crypto/ (one project)

ctf-crypto/SKILL.md

MITFull file

1# CTF Cryptography
2 
3Quick reference for crypto CTF challenges. Each technique has a one-liner here; see supporting files for full details with code.
4 
5## Prerequisites
6 
7**Python packages (all platforms):**
8```bash
9pip install pycryptodome z3-solver sympy gmpy2 hashpumpy fpylll py_ecc
10# Coppersmith (optional): pip install coppersmith
11# Alternative Coppersmith lib: git clone https://github.com/jvdsn/crypto-attacks ~/.ctf-tools/crypto-attacks && pip install -r ~/.ctf-tools/crypto-attacks/requirements.txt
12```
13 
14**Linux (apt):**
15```bash
16apt install hashcat
17```
18 
19**macOS (Homebrew):**
20```bash
21brew install hashcat
22```
23 
24**Manual install:**
25- SageMath (optional — only for legacy Sage fallback snippets (collapsed sections)) — Linux: `apt install sagemath`, macOS: `brew install --cask sage`
26- RsaCtfTool — `git clone https://github.com/RsaCtfTool/RsaCtfTool` (automated RSA attacks)
27- crypto-attacks (Coppersmith) — `git clone https://github.com/jvdsn/crypto-attacks ~/.ctf-tools/crypto-attacks` + `pip install -r ~/.ctf-tools/crypto-attacks/requirements.txt` (alternative to `pip install coppersmith`)
28 
29> **Note:** `gmpy2` requires libgmp — Linux: `apt install libgmp-dev`, macOS: `brew install gmp`.
30 
31## Additional Resources
32…

Excerpt shown under the repository's MIT license.

How to install ctf-crypto

ctf-crypto/SKILL.md

More skills in ctf-skills

Newsletter

Join the Community