CVE-2026-31900
criticalpriority · attend · 49EPSS 0.005 · 41 %ileexploit · PoCDEEUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixedpython313-black-0:25.1.0-160000.3.1.noarch as component of SUSE Linux Enterprise Server 16.0suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython313-black-0:25.1.0-160000.3.1.noarch as component of SUSE Linux Enterprise Server for SAP applications 16.0suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython311-black-0:26.3.1-1.1.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython311-black-0:26.3.1-1.1.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython311-black-0:26.3.1-1.1.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython311-black-0:26.3.1-1.1.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython313-black-0:26.3.1-1.1.aarch64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython313-black-0:26.3.1-1.1.ppc64le as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython313-black-0:26.3.1-1.1.s390x as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython313-black-0:26.3.1-1.1.x86_64 as component of openSUSE Tumbleweedsuse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
- Fixedpython313-black-0:25.1.0-160000.3.1.noarch as component of openSUSE Leap 16.0suse_csaf
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.4–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (1)
Public proof-of-concept and weaponised exploit code.
affected products (5)
Products and version ranges known to be affected.
advisories (6)
Vendor and ecosystem advisories describing this.
- SUSE-SU-2026:20928-1Security update for python-black2026-03-24csaf · suse_csafDE
Security update for python-black
- WID-SEC-W-2026-3046IBM Concert: Mehrere SchwachstellenDeutsch2026-08-26csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM Concert ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, um einen SQL-Injection Angriff durchzuführen und um Sicherheitsvorkehrungen zu umgehen.
- openSUSE-SU-2026:10372-1python311-black-26.3.1-1.1 on GA media2026-03-14csaf · suse_csafDE
python311-black-26.3.1-1.1 on GA media
- openSUSE-SU-2026:20417-1Security update for python-black2026-03-24csaf · suse_csafDE
Security update for python-black
- GHSA-v53h-f6m7-xcgmBlack's vulnerable version parsing leads to RCE in GitHub Action2026-03-07ghsa · osvUS
### Impact Black provides a [GitHub action](https://black.readthedocs.io/en/stable/integrations/github_actions.html) 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. ### Patches Version 26.3.0 fixes this vulnerability by tightening the validation of the `version` field. Users who use the GitHub Action as `psf/black@stable` will automatically pick up this update. ### Workarounds Do not use the `use_pyproject: true` option in the psf/black GitHub Action.
- PYSEC-2026-21202026-03-11vendor · osvUS
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.
also known as (6)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://black.readthedocs.io/en/stable/Patchcnnvd
- https://github.com/psf/black/commit/0a2560b981364dde4c8cf8ce9d164c40669a8611cnnvd
- https://github.com/psf/black/security/advisories/GHSA-v53h-f6m7-xcgmcnnvd
- https://vigilance.fr/vulnerability/Black-code-execution-via-GitHub-Action-50317cnnvd
- https://github.com/psf/black/commit/0a2560b981364dde4c8cf8ce9d164c40669a8611enisa_euvd
- https://github.com/psf/black/security/advisories/GHSA-v53h-f6m7-xcgmenisa_euvd
- https://github.com/psf/black/commit/0a2560b981364dde4c8cf8ce9d164c40669a8611Patchnvd
- https://github.com/psf/black/security/advisories/GHSA-v53h-f6m7-xcgmMitigationVendor Advisorynvd
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