CVE WatchOct 21, 2026

CVE-2026-96639

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

CVSS

9.8

Critical

EPSS

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KEV

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Exploit Today

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0-100

Published: Oct 21, 2026 · Last modified: Oct 21, 2026 · CWE-125 · CWE-787

EPSS · 30d

Not enough EPSS history yet.

Technical description

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.

Official references

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