CVE-2026-112401

Pillow is a Python imaging library. From 5.4.0 until 13.0.0, Pillow performs quadratic copying while parsing GIF comments. GifImageFile._seek() repeatedly appends immutable bytes for comment sub-blocks and multiple comment extensions, and frame zero is parsed during Image.open(). An attacker can submit a small-dimension GIF containing many comment extensions to any application that opens the file. This can consume excessive CPU and deny service before the application can inspect the image. This issue is fixed in version 13.0.0.

Score

CVSS 3.1 7.5 High

Status

Analyzed - security-advisories@github.com

Published

2026-10-19

Last modified

2026-10-27

Weaknesses

CWE-407

Affected products

• Pillow (Python)
• Pillow (Python-pillow)

References

• https://github.com/python-pillow/Pillow/security/advisories/GHSA-74r2-7ff9-mjj2
• https://github.com/python-pillow/Pillow/commit/68a3fe957d8a4d552e8c69d96066d749f0614c7e
• https://github.com/python-pillow/Pillow/releases/tag/13.0.0