Pillow: Out-of-bounds access in _imagingmorph on a zero-width image

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

Pillow is a Python imaging library. Prior to 13.0.0, Pillow's ImageMorph.MorphOp.apply() can access memory before a row buffer for a zero-width image. PPM and PGM input can create an image with width zero, and the native morphology routine indexes outrow[width - 1] without rejecting that geometry. An attacker can supply such an image to an application that applies a morphology operation. This can crash the process. This issue is fixed in version 13.0.0.

[ Fixes ]Fixes and patches

• Pillow 13.0.0Fixed version · GitHub Advisories · pip package Pillow: upgrade to 13.0.0 or later (affected <= 12.3.0)

[ Packages ]Affected open-source packages

• Pillow pipAffected <= 12.3.0 · fixed in 13.0.0 · GHSA-58r4-6rv3-gfh8

[ References ]References

• github.com/python-pillow/Pillow/commit/18f7c0dfee93063c51db6ed0ca8c4da2999dcb64
• github.com/python-pillow/Pillow/releases/tag/13.0.0
• github.com/python-pillow/Pillow/security/advisories/GHSA-58r4-6rv3-gfh8