# Pentest Ctf Crypto

> Cryptography tools for solving CTF challenges involving ciphers, hashing, and weak encryption.

- Skill: `jd-opensource/pentest-ctf-crypto` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add jd-opensource/pentest-ctf-crypto`
- Raw SKILL.md: https://api.skillmd.com/api/skills/jd-opensource/pentest-ctf-crypto/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: jd-opensource (https://skillmd.com/u/jd-opensource)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/jd-opensource/pentest-ctf-crypto

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# Pentest CTF Crypto

## Purpose
Analyze and break cryptographic implementations, including classical ciphers, RSA weak keys, and hash extensions.

## Core Workflow
1. **Cipher Identification**: Identify the type of encryption or encoding used (e.g., Base64, Caesar, RSA).
2. **Classical Cracking**: Brute-force or analyze frequency for classical ciphers using `ciphey` or online tools.
3. **RSA Attacks**: Check for common RSA weaknesses (small e, small factors) using `RsaCtfTool`.
4. **Hash Analysis**: Identify hash types and attempt cracking or length extension attacks using `hashcat` or `hashpump`.
5. **Math/Primes**: Solve mathematical problems related to cryptography using `sagemath`.

## References
- `references/tools.md`
- `references/workflows.md`