Individual skill
github-actions-hardening
Security hardening reviewer for GitHub Actions workflow files (.github/workflows/*.yml). Reasons about the Actions threat model that pattern matchers and general code linters miss — untrusted-input script injection, privileged triggers running fork code, mutable action references, and over-scoped tokens. Use this skill when asked to review, audit, harden, or secure a GitHub Actions workflow, when writing a new workflow, or for any request like "is this workflow safe?", "review my CI for security issues", "why is pull_request_target dangerous here?", "pin my actions", or "lock down GITHUB_TOKEN permissions". Covers script injection via ${{ }} interpolation, pull_request_target / workflow_run privilege escalation, SHA-pinning of third-party actions, least-privilege permissions, GITHUB_ENV/GITHUB_OUTPUT injection, secret exposure, OIDC over long-lived credentials, and self-hosted runner exposure on public repositories.
skills/github-actions-hardening/SKILL.md
Source commit edbecfa9099c4addae1f500cca1ac067204b30fd
What was checked
- Matches the observed repository HEAD
- Yes
- Scanner rules are current
- Yes
- Repository scan complete
- No
- Skill scan complete
- Yes
- Observed behavior
- Instructions only
- Last checked
- Nov 4, 2026
These are observations at the recorded commit, not a guarantee of safety. Review the source before running it.
Install this skill
Choose an agent in your Stack or copy a command below. Commands fetch the pinned commit and copy only this skill directory. Existing destinations are refused. Copying a command does not install anything.
An install command is unavailable: current rules, complete repository and skill scans, an eligible behavior level and a permitted license are required.
Repository context
- Repository stars (not skill ratings)
- 40,891
- Repository last updated
- Nov 6, 2026
- License
- MIT
Observed agent integration: No specific integration evidence. Standard SKILL.md installation does not imply verified compatibility.
- ai Repository topic
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- security Derived category
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Files and excerpt
File metadata and permitted, redacted excerpts come from the recorded scan. Source links are pinned to that commit.
Browse files
SKILL.mdcore · 9,852 bytesreferences/injection.mddoc · 3,035 bytesreferences/permissions-and-tokens.mddoc · 2,743 bytesreferences/report-format.mddoc · 1,920 bytesreferences/supply-chain.mddoc · 2,938 bytesreferences/triggers-and-privilege.mddoc · 3,397 bytes
Read excerpt
# GitHub Actions Hardening
A focused security reviewer for GitHub Actions workflows. It reasons about the *Actions-specific*
threat model — where trust boundaries live in trigger types, token scopes, and string
interpolation — rather than the application-code vulnerabilities a general security scanner looks
for. Most workflow risks are invisible to language linters because the dangerous code is the YAML
itself and the way GitHub expands `${{ }}` expressions into a shell before your script runs.
## When to Use This Skill
Use this skill when the request involves:
* Reviewing, auditing, or hardening any file under `.github/workflows/`
* Authoring a new workflow and wanting it secure by default