Harden GitHub Actions Workflow - scorecards.yml

[int-stepsecurity-advanced]

GitHub Token Permissions Are Not Set to Minimum in Workflow

Summary

The GitHub token permissions in your workflow file (.github/workflows/scorecards.yml) exceed the minimum required. Reducing permissions to the minimum necessary enhances security by limiting the access scope of the token, thereby lowering the risk of accidental or malicious misuse.

Why This is Important

Using excessive permissions in GitHub workflows can expose your repository to potential security risks. The GitHub token grants access to repository resources, and any unnecessary permissions increase the likelihood of sensitive actions being performed without justification. By applying the principle of least privilege, you protect your repository from unintended data exposure and ensure that each job only has access to what it absolutely needs.

Evidence of Excessive Permissions

For more context, please refer to the build log from your recent workflow run, which highlights the permissions granted to the GitHub token that exceed the recommended minimum.

Suggested Fix

Below is the updated permissions configuration, which minimizes access for the GitHub token. Update your workflow file with this suggested configuration to resolve this issue:

```diff
  # This workflow uses actions that are not certified by GitHub. They are provided
  # by a third-party and are governed by separate terms of service, privacy
  # policy, and support documentation.
  name: Scorecard supply-chain security
  on:
    # For Branch-Protection check. Only the default branch is supported. See
    # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
    branch_protection_rule:
    # To guarantee Maintained check is occasionally updated. See
    # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
    schedule:
      - cron: '20 7 * * 2'
    push:
      branches: ["main"]
  # Declare default permissions as read only.
  permissions: read-all
  jobs:
    analysis:
      name: Scorecard analysis
      runs-on: ubuntu-latest
      permissions:
        # Needed to upload the results to code-scanning dashboard.
        security-events: write
        # Needed to publish results and get a badge (see publish_results below).
        id-token: write
        contents: read
        actions: read
      steps:
        - name: Harden Runner
          uses: step-security/harden-runner@17d0e2bd7d51742c71671bd19fa12bdc9d40a3d6 # v2.8.1
          with:
            egress-policy: audit
        - name: "Checkout code"
          uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
          with:
            persist-credentials: false
        - name: "Run analysis"
          uses: ossf/scorecard-action@dc50aa9510b46c811795eb24b2f1ba02a914e534 # v2.3.3
          with:
            results_file: results.sarif
            results_format: sarif
            # (Optional) "write" PAT token. Uncomment the `repo_token` line below if:
            # - you want to enable the Branch-Protection check on a *public* repository, or
            # - you are installing Scorecards on a *private* repository
            # To create the PAT, follow the steps in https://github.com/ossf/scorecard-action#authentication-with-pat.
            # repo_token: ${{ secrets.SCORECARD_TOKEN }}
            # Public repositories:
            #   - Publish results to OpenSSF REST API for easy access by consumers
            #   - Allows the repository to include the Scorecard badge.
            #   - See https://github.com/ossf/scorecard-action#publishing-results.
            # For private repositories:
            #   - `publish_results` will always be set to `false`, regardless
            #     of the value entered here.
            publish_results: true
        # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
        # format to the repository Actions tab.
        - name: "Upload artifact"
          uses: actions/upload-artifact@0b2256b8c012f0828dc542b3febcab082c67f72b # v4.3.4
          with:
            name: SARIF file
            path: results.sarif
            retention-days: 5
        # Upload the results to GitHub's code scanning dashboard.
        - name: "Upload to code-scanning"
          uses: github/codeql-action/upload-sarif@4fa2a7953630fd2f3fb380f21be14ede0169dd4f # v3.25.12
          with:
            sarif_file: results.sarif

Next Steps

Please review and update the workflow file with these minimum permissions. If additional permissions are necessary for certain steps, specify only those permissions explicitly.

For further guidance, refer to the GitHub documentation on fine-grained permissions.

Severity: High