canonical/get-workflow-version-action can leak a partial GITHUB_TOKEN in exception output

Vulnerability Description

canonical/get-workflow-version-action is a GitHub composite action to get commit SHA that GitHub Actions reusable workflow was called with. Prior to 1.0.1, if the get-workflow-version-action step fails, the exception output may include the GITHUB_TOKEN. If the full token is included in the exception output, GitHub will automatically redact the secret from the GitHub Actions logs. However, the token may be truncated—causing part of the GITHUB_TOKEN to be displayed in plaintext in the GitHub Actions logs. Anyone with read access to the GitHub repository can view GitHub Actions logs. For public repositories, anyone can view the GitHub Actions logs. The opportunity to exploit this vulnerability is limited—the GITHUB_TOKEN is automatically revoked when the job completes. However, there is an opportunity for an attack in the time between the GITHUB_TOKEN being displayed in the logs and the completion of the job. Users using the github-token input are impacted. This vulnerability is fixed in 1.0.1.

References

• https://github.com/canonical/get-workflow-version-action/security/advisories/GHSA-26wh-cc3r-w6pj
• https://github.com/canonical/get-workflow-version-action/issues/2
• https://github.com/canonical/get-workflow-version-action/commit/88281a62e96e1c0ef4df30352ae0668a9f3e3369