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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/python-pillow/Pillow/commit/68a3fe957d8a4d552e8c69d96066d749f0614c7e Patch
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-74r2-7ff9-mjj2 Exploit, Patch, Vendor Advisory, Mitigation
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 8
- Cpes+1 CPE criteria (now 1)NVD modified 2026-10-27 21:02
- StatusPublished → AnalyzedNVD modified 2026-10-27 21:02
- StatusUndergoing Analysis → PublishedNVD modified 2026-10-20 16:09
- StatusPublished → Undergoing AnalysisNVD modified 2026-10-20 19:50
- StatusReceived → PublishedNVD modified 2026-10-20 16:09
- StatusPublished → ReceivedNVD modified 2026-10-20 17:17
- StatusReceived → PublishedNVD modified 2026-10-19 21:15
- First seenCVSS 6.9NVD modified 2026-10-19 22:17
Affected (CPE criteria) 1
cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*
References 3
- https://github.com/python-pillow/Pillow/commit/68a3fe957d8a4d552e8c69d96066d749f0614c7e Patch
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0 Release Notes
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-74r2-7ff9-mjj2 Exploit, Patch, Vendor Advisory, Mitigation