Vulnerability in Psf Black
CVE-2026-114134
Black is the uncompromising Python code formatter. Prior to 26.10.1, the Black GitHub Action with use_pyproject: true accepts tool.black.required-version from pyproject.toml without validating that it is a released Black version specifier. An attacker who can submit a pull request can change that field to a direct reference to attacker-controlled code, causing the workflow to install and execute the code in the victim repository's GitHub Actions context. This issue is fixed in version 26.10.1.
Published .
EPSS exploit prediction
EPSS: 0.004 (34.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 35th percentile — 34.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
The 30-day trend appears once there are two daily scores.
Affected products
- Psf Black — versions < 26.10.1