Pillow: TIFF encoder ColorMap plane-size mismatch causes a heap out-of-bounds read

[ 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 TIFF encoder can read beyond a ColorMap buffer when retained TIFF metadata has a plane size inconsistent with BitsPerSample. A small TIFF can be opened normally and then retain a crafted ColorMap that is reused when the image is saved. An application that re-encodes the attacker's TIFF with libtiff can trigger the out-of-bounds read. This can disclose heap memory in the output or 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-pchr-8j38-3x4p

[ References ]References

• github.com/python-pillow/Pillow/commit/d03dc3c587a9b0bdc9e4304d70d59a635a87b742
• github.com/python-pillow/Pillow/releases/tag/13.0.0
• github.com/python-pillow/Pillow/security/advisories/GHSA-pchr-8j38-3x4p