CI workflow RCE disclosed in OWASP BLT GitHub Actions

TL;DR — A pull_request_target GitHub Actions workflow in OWASP BLT can be turned into privileged CI RCE by copying attacker-controlled Django model code into the runner and invoking makemigrations, exposing GITHUB_TOKEN and secrets.

What happened

OWASP BLT is a QA testing and vulnerability disclosure platform that spans websites, apps, and Git repositories.

CVE-2026-40316 describes a GitHub Actions poisoned-pipeline RCE in BLT’s .github/workflows/regenerate-migrations.yml. The workflow uses the privileged pull_request_target trigger (base-repo context with write-capable GITHUB_TOKEN), copies attacker-controlled files from an untrusted PR into the runner workspace (via git show ... > ...), and then runs python manage.py makemigrations. Because Django imports model modules during migration generation, any module-level Python in an attacker-supplied website/models.py is executed during import, yielding arbitrary code execution on the runner.

The attack is triggerable by any external contributor who can open a PR, provided a maintainer applies the regenerate-migrations label. This is a common real-world failure mode in CI/CD: privileged triggers combined with unsafe “copy-from-PR then execute/build” patterns can convert routine maintainer actions (labeling/triage) into repo compromise and downstream supply-chain risk.

Who is impacted

• OWASP BLT (OWASP-BLT/BLT) deployments using the vulnerable workflow.

Notes for responders:

• The CVE record links to the GitHub Security Advisory GHSA-wxm3-64fx-cmx9, which describes this as an Actions workflow issue (not a runtime-only app bug), with impact centered on CI runner execution and secret exposure.

What to do now

• Follow project remediation guidance and apply the latest patched release available at the time of writing.

  "A patch for this issue is expected to be released in version 2.1.1."

• Treat this as a CI credential exposure / repo-compromise scenario if you suspect a malicious PR may have been processed: review recent workflow runs of .github/workflows/regenerate-migrations.yml, and rotate any credentials potentially accessible to the runner (including GITHUB_TOKEN-reachable tokens and Actions secrets).
• Reduce blast radius for similar patterns across your org:
  • Avoid using pull_request_target for workflows that copy/execute untrusted PR content.
  • Ensure workflow permissions: are least-privilege (especially contents: write) and gate maintainer label actions that trigger privileged workflows.