NetSight
high7.5

CVE-2026-112401

Pillow: Quadratic GIF comment concatenation allows DoS in Image.open()

Impact

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.

Affected packages

EcosystemPackageAffectedFixed in
pipPillow>= 5.4.0, < 13.0.013.0.0

Affected products

VendorProductAffected versions
PythonPillow
from 5.4.0 before 13.0.0

Weakness classification

References