ci: declare workflow-level contents: read on 6 lint/build workflows#6272
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arpitjain099 wants to merge 1 commit into
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ci: declare workflow-level contents: read on 6 lint/build workflows#6272arpitjain099 wants to merge 1 commit into
contents: read on 6 lint/build workflows#6272arpitjain099 wants to merge 1 commit into
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Pins the default GITHUB_TOKEN to contents: read on the 6 workflows in .github/workflows/ that don't actually need any write scope: - code-format.yml: prettier/clang-format check. - compiler-rs.yml: rust compiler build. - compiler.test.yml: spec compiler test matrix. - license.yml: license header check. - linter.yml: spec linter. - metamodel-sync.yml: copies compiler metamodel to ts generator and checks they're in sync with git status --porcelain; no GitHub API beyond the initial checkout. Left implicit on purpose: - backport.yml is on pull_request_target with a backport action. - generate.yml does git push. - update-rest-api-json.yml uses peter-evans/create-pull-request. - labeler.yml needs labeler write scope. Those four are best declared by a maintainer. Motivation: CVE-2025-30066 (March 2025 tj-actions/changed-files compromise) exfiltrated GITHUB_TOKEN from workflow logs. Per-workflow caps bound runtime authority irrespective of repo or org default, give drift protection if the default ever widens, and are credited per-file by the OpenSSF Scorecard Token-Permissions check. YAML validated locally with yaml.safe_load. Signed-off-by: Arpit Jain <arpitjain099@gmail.com>
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Pins the default
GITHUB_TOKENtocontents: readon the 6 workflows in.github/workflows/that don't actually need any write scope:code-format.yml: prettier / clang-format check.compiler-rs.yml: rust compiler build.compiler.test.yml: spec compiler test matrix.license.yml: license header check.linter.yml: spec linter.metamodel-sync.yml: copies the compiler metamodel to typescript-generator and checks they're in sync withgit status --porcelain. No GitHub API beyond the initial checkout.Left implicit on purpose:
backport.ymlis onpull_request_targetwith a backport action that needs write scope.generate.ymldoes agit push.update-rest-api-json.ymlusespeter-evans/create-pull-request.labeler.ymlneedspull-requests: write.Those four are best declared by a maintainer who owns the relevant flows.
Why
CVE-2025-30066 (March 2025
tj-actions/changed-filessupply-chain compromise) exfiltratedGITHUB_TOKENfrom workflow logs and the leaked token retained whatever scope was issued at the workflow level. Pinning per workflow caps that runtime authority irrespective of the repo or org default, gives drift protection if the default ever widens, and is credited per-file by the OpenSSF ScorecardToken-Permissionscheck.YAML validated locally with
yaml.safe_loadon each touched file.