CVE-2026-42309
5.5 · MEDIUMOverview
CVE-2026-42309 is a medium-severity vulnerability affecting python pillow. It was published on May 9, 2026 and has a CVSS 3.1 base score of 5.5 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.5, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical Description
Pillow is a Python imaging library. From version 11.2.1 to before version 12.2.0, 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 issue has been patched in version 12.2.0.
Remediation
Check the references section for vendor advisories and patches from python. Update pillow to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| python | pillow | >= 11.2.1, < 12.2.0 | Affected |
Frequently Asked Questions
What is CVE-2026-42309?
CVE-2026-42309 is a medium-severity vulnerability affecting python pillow. It was published on May 9, 2026 and has a CVSS 3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2026-42309?
This vulnerability has a CVSS 3.1 base score of 5.5, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-42309?
Check the references section for vendor advisories and patches from python. Update pillow to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-42309?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-42309 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
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