Defense-in-depth for the #2090-class incident (2026-04-24): GitHub's
hosted Copilot Coding Agent leaked a ghs_* installation token into
tenant-proxy/package.json via npm init slurping the URL from a
token-embedded origin remote. We can't fix upstream's clone hygiene,
so we gate at the PR layer.
Single workflow, dual purpose:
1. PR / push / merge_group gate on this repo (molecule-monorepo).
Refuses any change whose diff additions contain a credential-shaped
string. Same shape as Block forbidden paths — error message tells
the agent how to recover without echoing the secret value.
2. Reusable workflow entry point (workflow_call) for the rest of the
org. Other Molecule-AI repos enroll with a 3-line workflow:
jobs:
secret-scan:
uses: Molecule-AI/molecule-monorepo/.github/workflows/secret-scan.yml@main
This makes molecule-monorepo the single source of truth for the
regex set; consumer repos pick up new patterns without per-repo PRs.
Pattern set covers GitHub family (ghp_, ghs_, gho_, ghu_, ghr_,
github_pat_), Anthropic / OpenAI / Slack / AWS. Mirror of the
runtime's bundled pre-commit hook (molecule-ai-workspace-runtime:
molecule_runtime/scripts/pre-commit-checks.sh) — keep aligned when
either side adds a pattern.
Self-exclude on .github/workflows/secret-scan.yml so the file's own
regex literals don't block its merge.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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