GitHub Actions Security Audit

MCP server that audits .github/workflows/*.yml files for supply-chain risks. Catches script injection, leaked tokens, unpinned actions, broad permissions, and pull_request_target foot-guns — the patterns behind several 2024–2025 supply-chain incidents.

Built by Unbearable Labs. Pay-per-event — only billed when a tool is actually called.

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Available on

Apify Actor Store — primary, metered usage (PPE)
MCPize — pending submission
MCP.so — pending submission
PulseMCP — pending submission
Smithery — pending submission
Glama — pending submission

Newsletter: Unbearable TechTips Weekly · All Actors: github.com/UnbearableDev

What it does

Point any MCP-capable client (Claude Desktop, Cursor, n8n, Make, Zapier, custom agents) at this server, hand it a workflow YAML, and get back structured findings with:

Severity — critical / high / medium / low / info
Affected job and step — exact location of the problem
Description — why it matters, with the actual attack vector
Remediation — what to do about it
Fix snippet — YAML you can paste directly

Tools

| Tool | Purpose | |------|---------| | audit_workflow(workflow_yaml? \| workflow_url?, min_severity='low') | Run all checks | | check_secrets(...) | Secret-leakage paths only | | check_permissions(...) | GITHUB_TOKEN scope issues only | | check_action_pinning(...) | Action version-pinning only | | check_runner_security(...) | Self-hosted runner + script injection | | check_workflow_config(...) | Timeout / config hygiene | | check_supply_chain_advanced(...) | TeamPCP-class supply-chain patterns (GHA-201..208) | | list_checks(category?) | Browse the catalog |

Provide exactly one of workflow_yaml (paste the content) or workflow_url (HTTPS URL — typically a GitHub raw URL to a specific workflow file).

Check catalog (v2: 21 checks)

| ID | Category | Severity | Title | |----|----------|----------|-------| | GHA-001 | secrets | high | Secret interpolated directly into run: script | | GHA-002 | secrets | high | Secret printed via echo / set-output | | GHA-003 | secrets | medium | Secret used in if: condition | | GHA-004 | secrets | high | Hardcoded credential pattern in env: | | GHA-010 | permissions | high | permissions: write-all granted | | GHA-011 | permissions | medium | No top-level permissions: (inherits broad default) | | GHA-013 | permissions | high | pull_request_target + checkout PR head = PWNing pattern | | GHA-020 | action_pinning | high | Third-party action pinned to mutable tag | | GHA-021 | action_pinning | high | Third-party action pinned to mutable branch | | GHA-022 | action_pinning | medium | First-party action not SHA-pinned | | GHA-030 | runner_security | medium | Self-hosted runner used on pull_request from forks | | GHA-032 | runner_security | high | Script injection via untrusted github.event. interpolation | | GHA-040 | workflow_config | low | No timeout-minutes on job | | GHA-201 | supply_chain_advanced | high | Action pinned to unpinned branch ref (TeamPCP-class: @main/@master) | | GHA-202 | supply_chain_advanced | high | Action pinned to mutable tag — SHA pin recommended | | GHA-203 | supply_chain_advanced | critical | pull_request_target + checkout of PR head SHA/ref (codecov/tj-actions exploitation path) | | GHA-204 | supply_chain_advanced | high | Script injection via github.event. user-controlled field in run: | | GHA-205 | supply_chain_advanced | medium | Action from non-allowlisted owner (untrusted 3rd-party) | | GHA-206 | supply_chain_advanced | high | Top-level permissions: write-all or contents: write without per-job scoping | | GHA-207 | supply_chain_advanced | medium | Secret logged via echo / cat in run: block | | GHA-208 | supply_chain_advanced | low | Action uses a known-retired tag |

Pricing

| Event | USD | |-------|-----| | Any audit / check_* tool call | $0.02 | | list_checks discovery | $0.005 |

Connecting from Claude Desktop

{
  "mcpServers": {
    "gha-audit": {
      "transport": "streamable-http",
      "url": "https://YOUR-ACTOR-URL.apify.actor/mcp"
    }
  }
}

Sibling MCPs from Unbearable Labs

docker-compose-audit — docker-compose.yml security audit
dockerfile-audit — Dockerfile security & quality
hu-postcode-validator — Hungarian postcode lookup

What's NOT covered (yet)

Reusable workflow auditing (multi-file resolution)
CodeQL-grade dataflow tracking
Marketplace-listed action reputation scoring

Source / contact

Source: github.com/UnbearableDev/github-actions-audit. Issues + ideas: unbearabledev@gmail.com.

--- 📬 Built by Noel @ Unbearable Labs. More MCP servers + audit tips in the newsletter: https://unbearabletechtips.beehiiv.com

GitHub Actions Audit