Pin GitHub Actions to full-length commit SHAs

[Dan Fiedler (danfiedler-msft)]

Summary

This PR pins GitHub Actions to full-length commit SHAs for improved security and reproducibility and adds a 7 day cooldown to Dependabot configuration for GitHub Actions. This work is described in more detail at https://aka.ms/action-pinning.

Why?

Pinning actions to commit SHAs prevents supply-chain attacks where a tag could be moved to point to malicious code. This is a recommended security best practice per the GitHub Actions security hardening guide.

This change mitigates the risk of tag retargeting to malicious code as seen in incidents like the tj-actions/changed-files action compromise or codfish/semantic-release-action compromise and improves the integrity and reproducibility of the CI/CD pipeline.

What changed?

Action pinning: Third-party action references in .github/workflows/ that used mutable tag-based references (e.g., actions/checkout@v4) have been updated to full-length commit SHAs with a version comment (e.g., actions/checkout@<sha> # v4) using the pinact tool. References that were already pinned to a SHA, or that used immutable release tags, were left unchanged.

Dependabot configuration: .github/dependabot.yml has been updated to ensure a github-actions package-ecosystem section is present with a cooldown configuration (default-days: 7). If the file did not exist, it was created. If a github-actions section already existed, only the cooldown block was added or its default-days value was increased to 7 if it was lower. The 7-day cooldown provides a window for the community to detect and report compromised releases before they are automatically proposed as updates, reducing exposure to supply-chain attacks via newly published malicious versions.

Is this safe to merge?

Yes. The pinned SHAs correspond to the same commits that the existing tags pointed to. No behavioral changes in action execution are introduced. You can verify the pinned SHA value using the GitHub REST API (e.g., the commit hash for actions/checkout@v7 can be found in the sha property in the JSON response for GET https://api.github.com/repos/actions/checkout/commits/v7).

Additional Information

For more information, please see https://aka.ms/action-pinning

[github-actions]

🔒 AI Validation Pending

This PR is from an external contributor. AI validation will be performed after manual review.

Maintainers: Add the external-approved label to enable AI validation.

[Copilot]

Pull request overview

Hardens CI supply-chain security by pinning GitHub Actions to immutable commit SHAs and configuring delayed Dependabot updates.

Changes:

• Pins action references while retaining version comments.
• Adds weekly grouped GitHub Actions updates with a seven-day cooldown.
• One mutable action reference remains in production-build.yml.

Reviewed changes

Copilot reviewed 25 out of 25 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
.github/dependabot.yml	Adds GitHub Actions updates and cooldown.
.github/workflows/Deploy-Documentation.yml	Pins documentation deployment actions.
.github/workflows/Deploy-Standalone.yml	Pins standalone deployment actions.
.github/workflows/ISSUE_MANAGEMENT.yml	Pins stale-issue actions.
.github/workflows/check-ai-docs.yml	Pins checkout.
.github/workflows/codeql-analysis.yml	Pins CodeQL actions.
.github/workflows/compile-loc.yml	Pins localization workflow actions.
.github/workflows/copilot-cleanup.yml	Pins cleanup workflow actions.
.github/workflows/copilot-design-pass.yml	Pins checkout.
.github/workflows/copilot-flake-review.yml	Pins flake-review actions.
.github/workflows/copilot-investigate.yml	Pins checkout references.
.github/workflows/copilot-resolve-conflicts.yml	Pins checkout.
.github/workflows/loc-auto-merge.yml	Pins checkout.
.github/workflows/playwright.yml	Pins Playwright workflow actions.
.github/workflows/pr-ai-validation.yml	Pins validation workflow actions.
.github/workflows/pr-coverage.yml	Pins coverage workflow actions.
.github/workflows/private-vsix-build.yml	Pins private build actions.
.github/workflows/production-build.yml	Pins most production actions; one remains mutable.
.github/workflows/real-e2e.yml	Pins live E2E workflow actions.
.github/workflows/test.yml	Pins test workflow actions.
.github/workflows/update-changelog.yml	Pins changelog workflow actions.
.github/workflows/update-knowledge-graphs.yml	Pins graph update actions.
.github/workflows/upload-templates.yml	Pins template upload actions.
.github/workflows/version-release.yml	Pins release workflow actions.
.github/workflows/vscode-e2e.yml	Pins VS Code E2E actions.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.