Pillow is a Python imaging library. From 11.0.0 until 13.0.0, multi-frame loaders can retain an ImagingCore allocation created for a narrow frame mode while a later frame of the same dimensions changes the logical mode and decoder tiles to wider RGB or CMYK data. ImageFile.load_prepare() reuses the stale native storage because _im is non-null without verifying that its mode and size still match. Crafted PSD, MPO, DCX, or MIC frame transitions can then write wider pixels into the narrow allocation, causing native out-of-bounds writes and crashes. The MPO path can also cause a native over-read and, in demonstrated runtime-specific profiles, command execution. 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/78d97d994579aef81aafe123773d525f40f2522a Patch
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-v9pv-5gc8-w2m6 Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 5
- Cpes+1 CPE criteria (now 1)NVD modified 2026-10-27 14:25
- StatusAwaiting Analysis → AnalyzedNVD modified 2026-10-27 14:25
- StatusPublished → Awaiting AnalysisNVD modified 2026-10-22 16:46
- StatusReceived → PublishedNVD modified 2026-10-21 21:06
- First seenCVSS 9.8NVD modified 2026-10-21 21:20
Affected (CPE criteria) 1
cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*
References 4
- https://github.com/python-pillow/Pillow/commit/78d97d994579aef81aafe123773d525f40f2522a Patch
- https://github.com/python-pillow/Pillow/pull/10105 Issue Tracking
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0 Release Notes
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-v9pv-5gc8-w2m6 Vendor Advisory