CVE-2026-112401 — Pillow: Quadratic GIF comment concatenation allows DoS in Image.open()
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 byte…
Published: 2026-10-19 · CVSS: 6.9 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7