Ctf Crypto
Curated cryptanalysis attack index for CTF crypto: RSA, ECC, AES, lattices, PRNG, ZKP
Test report
- Verdict
- Tested · Works
- Score
- Tested
- Jul 20, 2026
- Environment
- Claude Code 2.x (agent harness)
- Upstream re-checked
- Aug 10, 2026 · b97921e
Fetched the repo tree and read ctf-crypto/SKILL.md (319 lines) plus spot-checked modern-ciphers.md and rsa-attacks.md; every one of the 16 relative links resolves to a real file in the tree, frontmatter parses with name+description, and a security grep found no curl|sh, base64, exfil, or injected instructions (only standard pip/apt/brew installs and an optional RsaCtfTool git clone). Trigger phrasings judged — ACTIVATE: "solve this RSA challenge where n's two primes are really close", "AES-GCM oracle reuses the same nonce, how do I forge a tag?", "recover the LFSR keystream from the known file header"; NOT: "set up a TLS cert for my nginx server" (ops crypto, not cryptanalysis), "reverse engineer this stripped ELF to find the license check" (belongs to ctf-reverse) — 5/5 correct. I verified python3+sympy is present and ran the Fermat technique successfully, confirming the runtime is self-contained.
Scored on four weighted criteria — install, triggering, output vs. baseline, docs. How scoring works
- Installs cleanly 5/5
- Triggers reliably 5/5
- Output vs. baseline 7/10
- Docs & honesty 5/5
What Ctf Crypto does
A reference skill that routes CTF cryptography challenges to the right attack, with a one-liner per technique and pointers to 16 detail files carrying worked code (RSA, ECC, AES modes, lattice/LWE, PRNG, ZKP, exotic algebra). Triggers when attacking encryption, hashing, signatures, PRNGs, or number-theoretic crypto in a CTF context. It is guidance, not an executable tool — the code examples assume python3/sympy/SageMath are present.
How to install Ctf Crypto
Copy the ctf-crypto/ directory (SKILL.md + the 16 .md files) into your agent's skills folder, e.g. ~/.claude/skills/ctf-crypto/. For the code examples: pip install pycryptodome z3-solver sympy gmpy2; SageMath and RsaCtfTool are optional for lattice/ECC/automated-RSA work.
Skills live in ~/.claude/skills/ (global) or .claude/skills/
(per-project). Restart Claude Code after installing.
Commands — how to trigger Ctf Crypto
-
/ctf-cryptoCurated cryptanalysis attack index for CTF crypto: RSA, ECC, AES, lattices, PRNG, ZKP
It also activates on plain-language prompts like these:
-
Break this RSA challenge with a small public exponent -
Solve this padding oracle attack for the CTF -
Find the Wiener attack weakness in this key
Frequently asked questions
- Is the Ctf Crypto skill free?
- Yes. The skill itself is free from ljagiello/ctf-skills. SkillProof publishes the install command and an independent test verdict at no cost.
- Does Ctf Crypto work with Claude Code?
- We tested it with Claude Code 2.x (agent harness) on Jul 20, 2026. Verdict: Tested · Works. Fetched the repo tree and read ctf-crypto/SKILL.md (319 lines) plus spot-checked modern-ciphers.md and rsa-attacks.md; every one of the 16 relative links resolves to a real file in the tree, frontmatter parses with name+description, and a security grep found no curl|sh, base64, exfil, or injected instructions (only standard pip/apt/brew installs and an optional RsaCtfTool git clone). Trigger phrasings judged — ACTIVATE: "solve this RSA challenge where n's two primes are really close", "AES-GCM oracle reuses the same nonce, how do I forge a tag?", "recover the LFSR keystream from the known file header"; NOT: "set up a TLS cert for my nginx server" (ops crypto, not cryptanalysis), "reverse engineer this stripped ELF to find the license check" (belongs to ctf-reverse) — 5/5 correct. I verified python3+sympy is present and ran the Fermat technique successfully, confirming the runtime is self-contained.
- What is the Ctf Crypto SkillProof Score?
- 8.8/10 — installs cleanly 5/5, triggers reliably 5/5, output vs. baseline 7/10, docs & honesty 5/5.
- How do I install Ctf Crypto?
- Copy the install command from this page, run it in your terminal, and restart Claude Code. Skills live in ~/.claude/skills/ (global) or .claude/skills/ inside a project.
- Can I use Ctf Crypto with Cursor, Copilot, Gemini CLI, Codex or other AI tools?
- The SKILL.md format is native to Claude (Claude Code, Desktop, claude.ai). The instructions inside adapt to other assistants: Cursor rules, GitHub Copilot instructions, Windsurf rules, Custom GPTs, AGENTS.md for OpenAI Codex, and GEMINI.md for Google Gemini CLI — our conversion guides cover each, and the free converter on the tools page does the wrapping for you.