Dependency Pinning

How GitHub Actions Mutable Action Tags Enable Supply-Chain Attacks and How to Fix Them

A GitHub Actions workflow was using `actions/checkout@v1`, a mutable tag reference that could be silently repointed by the action owner to inject malicious code. This supply-chain vulnerability was fixed by pinning the action to a specific commit SHA (`11bd71901bbe5b1630ceea73d27597364c9af683`), ensuring the workflow always executes verified, immutable code.