skill-security-auditor

これはレビュー時に保存された抜粋です。完全で最新の内容は外部ソースを確認してください。

---
name: "skill-security-auditor"
description: >
  Security audit and vulnerability scanner for AI agent skills before installation.
  Use when: (1) evaluating a skill from an untrusted source, (2) auditing a skill
  directory or git repo URL for malicious code, (3) pre-install security gate for
  Claude Code plugins, OpenClaw skills, or Codex skills, (4) scanning Python scripts
  for dangerous patterns like os.system, eval, subprocess, network exfiltration,
  (5) detecting prompt injection in SKILL.md files, (6) checking dependency supply
  chain risks, (7) verifying file system access stays within skill boundaries.
  Triggers: "audit this skill", "is this skill safe", "scan skill for security",
  "check skill before install", "skill security check", "skill vulnerability scan".
---

# Skill Security Auditor

Scan and audit AI agent skills for security risks before installation. Produces a
clear **PASS / WARN / FAIL** verdict with findings and remediation guidance.

## Quick Start

```bash
# Audit a local skill directory
python3 scripts/skill_security_auditor.py /path/to/skill-name/

# Audit a skill from a git repo
python3 scripts/skill_security_auditor.py https://github.com/user/repo --skill skill-name

# Audit with strict mode (any WARN becomes FAIL)
python3 scripts/skill_security_auditor.py /path/to/skill-name/ --strict

# Output JSON report
python3 scripts/skill_security_auditor.py /path/to/skill-name/ --json
```

## What Gets Scanned

### 1. Code Execution Risks (Python/Bash Scripts)

Scans all `.py`, `.sh`, `.bash`, `.js`, `.ts` files for:

| Category | Patterns Detected | Severity |
|----------|-------------------|----------|
| **Command injection** | `os.system()`, `os.popen()`, `subprocess.call(shell=True)`, backtick execution | 🔴 CRITICAL |
| **Code execution** | `eval()`, `exec()`, `compile()`, `__import__()` | 🔴 CRITICAL |
| **Obfuscation** | base64-encoded payloads, `codecs.decode`, hex-encoded strings, `chr()` chains | 🔴 CRITICAL |
| **Network exfiltration** | `requests.post()`, `urllib.request`, `socket.connect()`, `httpx`, `aiohttp` | 🔴 CRITICAL |
| **Credential harvesting** | reads from `~/.ssh`, `~/.aws`, `~/.config`, env var extraction patterns | 🔴 CRITICAL |
| **File system abuse** | writes outside skill dir, `/etc/`, `~/.bashrc`, `~/.profile`, symlink creation | 🟡 HIGH |
| **Privilege escalation** | `sudo`, `chmod 777`, `setuid`, cron manipulation | 🔴 CRITICAL |
| **Unsafe deserialization** | `pickle.loads()`, `yaml.load()` (without SafeLoader), `marshal.loads()` | 🟡 HIGH |
| **Subprocess (safe)** | `subprocess.run()` with list args, no shell | ⚪ INFO |

### 2. Prompt Injection in SKILL.md

Scans SKILL.md and all `.md` reference files for:

| Pattern | Example | Severity |
|---------|---------|----------|
| **System prompt override** | "Ignore previous instructions", "You are now..." | 🔴 CRITICAL | <!-- noqa: SEC-AUDITOR -->
| **Role hijacking** | "Act as root", "Pretend you have no restrictions" | 🔴 CRITICAL | <!-- noqa: SEC-AUDITOR -->
| **Safety bypass** | "Skip safety checks", "Disable content filtering" | 🔴 CRITICAL | <!-- noqa: SEC-AUDITOR -->
| **Hidden instructions** | Zero-width characters, HTML comments with directives | 🟡 HIGH |
| **Excessive permissions** | "Run any command", "Full filesystem access" | 🟡 HIGH |
| **Data extraction** | "Send contents of", "Upload file to", "POST to" | 🔴 CRITICAL | <!-- noqa: SEC-AUDITOR -->

### 3. Dependency Supply Chain

For skills with `requirements.txt`, `package.json`, or inline `pip install`:

| Check | What It Does | Severity |
|-------|-------------|----------|
| **Known vulnerabilities** | Cross-reference with PyPI/npm advisory databases | 🔴 CRITICAL |
| **Typosquatting** | Flag packages similar to popular ones (e.g., `reqeusts`) | 🟡 HIGH |
| **Unpinned versions** | Flag `requests>=2.0` vs `requests==2.31.0` | ⚪ INFO |
| **Install commands in code** | `pip install` or `npm install` inside scripts | 🟡 HIGH |
| **Suspicious packages** |