ctf-crypto SKILL.md skillA
This file is byte-identical to the first copy the registry indexed, one of 3 indexed copies. Same content hash, so the same checks give both the same grade.
ctf-crypto from naravid19/claude-ctf-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add naravid19/claude-ctf-skills/ctf-crypto@git:20260927.84043a0Pins git:20260927.84043a0 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- naravid19/claude-ctf-skills
- Path
skills/ctf-crypto/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260927.84043a0, committed Sep 27, 2026
- First version recorded
- Sep 8, 2026
- Size
- 42,044 bytes
- Repository stars
- 4
- License
- MIT
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.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# CTF Cryptography Quick reference for crypto CTF challenges. Each technique has a one-liner here; see supporting files for full details with code. ## Prerequisites **Python packages (all platforms):** ```bash pip install pycryptodome z3-solver sympy gmpy2 hashpumpy fpylll py_ecc # Coppersmith (optional): pip install coppersmith # Alternative Coppersmith lib: git clone https://github.com/jvdsn/crypto-attacks ~/.ctf-tools/crypto-attacks && pip install -r ~/.ctf-tools/crypto-attacks/requirements.txt ``` **Linux (apt):** ```bash apt install hashcat ``` **macOS (Homebrew):** ```bash brew install hashcat ``` **Manual install:** - SageMath (optional — only for legacy Sage fallback snippets (collapsed sections)) — Linux: `apt install sagemath`, macOS: `brew install --cask sage` - RsaCtfTool — `git clone https://github.com/RsaCtfTool/RsaCtfTool` (automated RSA attacks) - 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`) > **Note:** `gmpy2` requires libgmp — Linux: `apt install libgmp-dev`, macOS: `brew install gmp`. …
Read the whole file at its exact version.
How to install
mdr add naravid19/claude-ctf-skills/ctf-crypto@sha256:3f73227dbf2b12c0The line at the top of this page pins the label git:20260927.84043a0, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_oyggbmllfrbis7q6)
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Versions
The registry has recorded 2 versions of this file, between Sep 8, 2026 and Sep 27, 2026, about one every 19 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260927.84043a0 latest | 2026-09-27 | 84043a0 | 42,044 B | A | view · diff |
| git:20260908.0cdca9b | 2026-09-08 | 0cdca9b | 38,930 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (42044 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
naravid19/claude-ctf-skills · 4 stars · license MIT · pushed 2026-10-24 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_oyggbmllfrbis7q6 GET https://markdownregistry.com/api/v1/resolve?ref=naravid19/claude-ctf-skills/ctf-crypto GET https://markdownregistry.com/api/v1/blob/3f73227dbf2b12c063d8df68a207430dfe1113f290a9da0fe2715f73fc74259c
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
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