Build: Limit permissions for GitHub workflows

sashashura · mgol · commit 0d9fae4c3acc · 2022-12-01T14:27:11.000+01:00
Add explicit permissions section[^1] to workflows. This is a security best practice because by default workflows run with extended set of permissions[^2] (except from `on: pull_request` from external forks[^3]. By specifying any permission explicitly all others are set to none. By using the principle of least privilege the damage a compromised workflow can do (because of an injection[^4] or compromised third party tool or action) is restricted. It is recommended to have most strict permissions on the top level[^5] and grant write permissions on job level[^6] on a case by case basis. [^1]: https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#permissions [^2]: https://docs.github.com/en/actions/security-guides/automatic-token-authentication#permissions-for-the-github_token [^3]: https://securitylab.github.com/research/github-actions-preventing-pwn-requests/ [^4]: https://securitylab.github.com/research/github-actions-untrusted-input/ [^5]: https://github.com/ossf/scorecard/blob/main/docs/checks.md#token-permissions [^6]: https://docs.github.com/en/actions/using-jobs/assigning-permissions-to-jobs Closes gh-5119 (cherry picked from commit c909d6b)
diff --git a/.github/workflows/node.js.yml b/.github/workflows/node.js.yml
@@ -2,6 +2,9 @@ name: CI
 
 on: [push, pull_request]
 
+permissions:
+  contents: read # to fetch code (actions/checkout)
+
 jobs:
   build:
     runs-on: ubuntu-latest
