Description
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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| psf | black | < 26.10.1 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | black | 26.10.1-1 | — |
| Debian 13 | black | No fix yet | — |
| Debian 12 | black | No fix yet | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | open-webui | 0.12.3-r10 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | black | < 26.10.1 | 26.10.1 | GHSA-cg8m-r9f2-5wm2 |