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

[azure-pipelines]

Azure Pipelines:
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[github-actions]

check-spelling-bot Report

🔴 Please review

See the 📂 files view, the 📜action log, 👼 SARIF report, or 📝 job summary for details.

Unrecognized words (1)

cooldown

To accept these unrecognized words as correct, you could run the following commands

... in a clone of the git@github.com:danfiedler-msft/terminal.git repository
on the danfiedler/pin-actions branch (ℹ️ how do I use this?):

curl -s -S -L 'https://raw.githubusercontent.com/check-spelling/check-spelling/cfb6f7e75bbfc89c71eaa30366d0c166f1bd9c8c/apply.pl' |
perl - 'https://github.com/microsoft/terminal/actions/runs/32173350669/attempts/1' &&
git commit -m 'Update check-spelling metadata'

Available 📚 dictionaries could cover words (expected and unrecognized) not in the 📘 dictionary

This includes both expected items (2022) from .github/actions/spelling/expect/alphabet.txt .github/actions/spelling/expect/expect.txt .github/actions/spelling/expect/web.txt and unrecognized words (1)

Dictionary	Entries	Covers	Uniquely
cspell:cpp/src/lang-keywords.txt	44	3	3
cspell:csharp/csharp.txt	32	2	2
cspell:cpp/src/compiler-clang-attributes.txt	46	2	2
cspell:aws/aws.txt	218	2	2
cspell:python/src/python/python.txt	392	2	2

Consider adding to the extra_dictionaries array (in the .github/actions/spelling/config.json file):

    "cspell:cpp/src/lang-keywords.txt",
    "cspell:csharp/csharp.txt",
    "cspell:cpp/src/compiler-clang-attributes.txt",
    "cspell:aws/aws.txt",
    "cspell:python/src/python/python.txt",

To stop checking additional dictionaries, put (in the .github/actions/spelling/config.json file):

"check_extra_dictionaries": []

✏️ Contributor please read this

By default the command suggestion will generate a file named based on your commit. That's generally ok as long as you add the file to your commit. Someone can reorganize it later.

If the listed items are:

• ... misspelled, then please correct them instead of using the command.
• ... names, please add them to .github/actions/spelling/allow/names.txt.
• ... APIs, you can add them to a file in .github/actions/spelling/allow/.
• ... just things you're using, please add them to an appropriate file in .github/actions/spelling/expect/.
• ... tokens you only need in one place and shouldn't generally be used, you can add an item in an appropriate file in .github/actions/spelling/patterns/.

See the README.md in each directory for more information.

🔬 You can test your commits without appending to a PR by creating a new branch with that extra change and pushing it to your fork. The check-spelling action will run in response to your push -- it doesn't require an open pull request. By using such a branch, you can limit the number of typos your peers see you make. 😉

If the flagged items are 🤯 false positives

If items relate to a ...

• binary file (or some other file you wouldn't want to check at all).

  Please add a file path to the excludes.txt file matching the containing file.

  File paths are Perl 5 Regular Expressions - you can test yours before committing to verify it will match your files.

  ^ refers to the file's path from the root of the repository, so ^README\.md$ would exclude README.md (on whichever branch you're using).

• well-formed pattern.

  If you can write a pattern that would match it,
  try adding it to the patterns.txt file.

  Patterns are Perl 5 Regular Expressions - you can test yours before committing to verify it will match your lines.

  Note that patterns can't match multiline strings.

[Leonard Hecker (lhecker)]

Should we upgrade the dependency when we're at it?

[Leonard Hecker (lhecker)]

The word ("cooldown") should go into .github/actions/spelling/expect/expect.txt. The file is sorted alphabetically.