What’s Vulnerable › Vulnerabilities

CVE-2026-112901: Pillow: ReDoS in XbmImagePlugin: 512-byte file stalls Image.open() for minutes

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-10-19 · updated 2026-10-27
• Weakness: CWE-1333

Description

Pillow is a Python imaging library. Prior to 13.0.0, Pillow's XBM header parser is vulnerable to regular-expression denial of service. In XbmImageFile._open, when an application calls Image.open() on a small crafted XBM file, XbmImagePlugin applies a backtracking expression to the attacker-controlled header before image dimensions are accepted, stalling a worker for minutes and denying service. This issue is fixed in version 13.0.0.

Affected products

• python-pillow Pillow: before 13.0.0 — fixed in 13.0.0
• Pypi Pillow: before 13.0.0; 1.0, 1.1, 1.2, 1.3, 1.4, 1.5 (+101) — fixed in 13.0.0
• python-pillow Pillow: before 13.0.0

How to fix

Upgrade to a fixed version: python-pillow Pillow 13.0.0; Pypi Pillow 13.0.0. Check the vendor advisory for mitigations.

References

• https://github.com/python-pillow/Pillow/commit/2852a3e3d568997ddec745fc800991f138878f4b
• https://github.com/python-pillow/Pillow/releases/tag/13.0.0
• https://github.com/python-pillow/Pillow/security/advisories/GHSA-xgh8-jp6q-p5x8

Get alerted when CVE-2026-112901 or the next vulnerability affects your stack