CVE-2026-114134
### Summary The GitHub Action bundled with Black can read the version from `tool.black.required-version` if `use_pyproject` is set to True. This version is not validated and therefore can be used to execute untrusted code in the context of a victim's repository. ### Details This is similar to the previous CVE-2026-31900. The value in `tool.black.required-version` is accepted as the version to be installed by the action without validation. ### Proof of concept Reproduction requires a victim to use Black's GitHub Action with `use_pyproject: true`. The attacker would then issue a PR to the victim's repository with `pyproject.toml` edited so that Black points to a malicious repository. ### Impact This is a remote code execution vulnerability impacting users using the GitHub Action bundled with psf/black and using the `use_pyproject: true` setting.
Properties
- Ghsa id
- GHSA-cg8m-r9f2-5wm2
- Summary
- Black: GitHub Action installs unvalidated required-version from pyproject.toml
- Severity
- high
- Last source
- GitHub Advisory Database
- Cve id
- CVE-2026-114134
- First seen by Signal
- 2026-10-22T18:12:38+00:00
- Is ghsa only
- false
- Retrieved at
- 2026-10-22T22:16:44+00:00
- Ghsa published
- 2026-10-22T16:18:57Z
- Source url
- https://github.com/advisories/GHSA-cg8m-r9f2-5wm2
- Ghsa updated
- 2026-10-22T16:18:58Z
Related Entities (3)
AFFECTS (1)
HAS_WEAKNESS (1)
VULNERABLE_TO (1)
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