CVE-2026-31900

Black is the uncompromising Python code formatter. Black provides a GitHub action for formatting code. This action supports an option, use_pyproject: true, for reading the version of Black to use from the repository pyproject.toml. A malicious pull request could edit pyproject.toml to use a direct URL reference to a malicious repository. This could lead to arbitrary code execution in the context of the GitHub Action. Attackers could then gain access to secrets or permissions available in the context of the action. Version 26.3.0 fixes this vulnerability.

CVSS

No CVSS.

References

Link	Resource
https://github.com/psf/black/commit/0a2560b981364dde4c8cf8ce9d164c40669a8611
https://github.com/psf/black/security/advisories/GHSA-v53h-f6m7-xcgm

Configurations

No configuration.

History

11 Mar 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-11 20:16

Updated : 2026-03-12 21:08

NVD link : CVE-2026-31900

Mitre link : CVE-2026-31900

CVE.ORG link : CVE-2026-31900

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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