CTF Skills

Install

npx skills add ljagiello/ctf-skills

This is third-party code. Review the repository files before installing.

What it does

Eleven CTF category skills with detailed techniques: SQLi and SSTI, ROP and heap exploitation, RSA and ECC attacks, binary and VM reversing, steganography, OSINT and malware analysis. The solve-challenge skill triages a challenge and routes it to the right specialist skill; ctf-writeup produces a submission-style writeup. It ships a grouped tool installer script and pwntools templates.

Who it is for. CTF players and security practitioners training on challenge tasks.

Example request

/solve-challenge here is the binary and the service address, find the vulnerability and get the flag

Limitations

Many techniques need external tools installed by install_ctf_tools.sh via pip, apt, brew, gems and go. The pat mode clones PayloadsAllTheThings into ~/.ctf-tools. Skills assume a filesystem-based agent with bash, Python 3 and internet access.

How to disable. Remove the ctf-* and solve-challenge folders from your agent's skills directory. Installed tools and logs live in ~/.ctf-tools.

Security check

• The installer adds many system packages and tools
• Skills run exploits, arbitrary shell commands and network attacks

README in short

ctf-skills is a set of Agent Skills for solving CTF challenges, compatible with Claude Code and other hosts of the standard. It installs via npx skills add. The README describes two setup strategies: pre-install tools with the installer script or install on demand. A skills table lists techniques per category. MIT licensed.

SKILL.md

---
name: solve-challenge
description: Solves CTF challenges by performing first-pass triage, identifying the dominant category, and routing execution to the right specialized ctf-* skill. Use when the user gives you a challenge bundle, a remote service, a suspicious file, or only a vague challenge description and you must determine where to start. Do not use it when the category is already clear and a specialized skill can be invoked directly; this is the dispatcher and recon entrypoint, not the deepest reference for category-specific techniques.
license: MIT
compatibility: Requires filesystem-based agent (Claude Code or similar) with bash, Python 3, and internet access. Orchestrates other ctf-* skills.
allowed-tools: Bash Read Write Edit Glob Grep Task WebFetch WebSearch Skill
metadata:
  user-invocable: "true"
  argument-hint: "[category] [challenge-file-or-url]"
---

# CTF Challenge Solver

You're a skilled CTF player. Your goal is to solve the challenge and find the flag.

## Environment Setup

Two setup strategies depending on your workflow:

### Pre-install (recommended before competitions)

Use the central installer entrypoint:

```bash
bash scripts/install_ctf_tools.sh all
```

Run a narrower mode when you only want one tool group:

```bash
bash scripts/install_ctf_tools.sh python
bash scripts/install_ctf_tools.sh apt
bash scripts/install_ctf_tools.sh brew
bash scripts/install_ctf_tools.sh gems
bash scripts/install_ctf_tools.sh go
bash scripts/install_ctf_tools.sh manual
```

The full package lists now live in [scripts/install_ctf_tools.sh](../scripts/install_ctf_tools.sh).

### On-demand (during challenges)

Each category skill's `SKILL.md` has a **Prerequisites** section listing only the tools needed for that category. Install as you go.

## Workflow

### Step 0: CTFd Platform Detection

If the CTF platform URL is known, check if it runs CTFd and switch to API-driven navigation:

```bash
# Detect CTFd (look for /api/v1/ and /themes/core/)
curl -s "$CTF_URL/api/v1/" | head -5
curl -s "$CTF_URL" | grep -oE '/themes/core/'
```

If CTFd is detected, **ask the user for their API token** (generated from CTFd Settings > Access Tokens). The token is not provided by default — the user must create one in the CTFd web UI first. Once provided, set the environment variables and proceed via API:

```bash
export CTF_URL="https://ctf.example.com"

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