GitHub Advisoryadvisory · PyPI
GHSA-5xmw-vc9v-4wf2 Pillow has a heap buffer overflow with nested list coordinates
MEDIUM
Official page ↗
- Aliases
- CVE-2026-42309
- Ecosystem
- PyPI
- Packages
- pillow
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-122
- Reviewed
- 2026-05-04
Affected packages
• PyPI pillow: >= 11.2.1, < 12.2.0 → fixed in 12.2.0
Description
Passing nested lists as coordinates to APIs that accept coordinates such as `ImagePath.Path`, `ImageDraw.ImageDraw.polygon` and `ImageDraw.ImageDraw.line` could cause a heap buffer overflow, as nested lists were recursively unpacked beyond the allocated buffer. Coordinate lists are now validated to contain exactly two numeric coordinates. This was introduced in Pillow 11.2.1.
Related
Alias · CVE (1)
- CVE-2026-42309 Pillow is a Python imaging library. vulnerability
Weakness · CWE (1)
- CWE-122 Heap-based Buffer Overflow weakness
References
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-5xmw-vc9v-4wf2 web
- https://nvd.nist.gov/vuln/detail/CVE-2026-42309 advisory
- https://github.com/designcomputer/mysql_mcp_server/commit/a96549f4a4d65443fd6e9c7f2324fba9a5c80a82 web
- https://github.com/python-pillow/Pillow/commit/cf6de8ca9b23e714aa5310e1c791eda66fc0b670 web
- https://github.com/pypa/advisory-database/tree/main/vulns/pillow/PYSEC-2026-2251.yaml web
- https://github.com/python-pillow/Pillow package
- https://github.com/python-pillow/Pillow/releases/tag/12.2.0 web