Pillow: TiffDecode returns uninitialized memory as pixels for short JPEG strips

[ Why it matters ]Priority signals

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

[ Description ]Official description

Pillow is a Python imaging library. From 5.3.0 until 13.0.0, Pillow can return uninitialized memory as pixels when libtiff performs a short decode of JPEG-compressed or Group 4 fax TIFF data. The _decodeStrip and _decodeTile buffers can be larger than the bytes written by libtiff, but Pillow converts the expected rows without clearing the unwritten tail. The tile path is affected from 5.3.0 and the strip path from 6.0.0. An attacker can supply a crafted TIFF to an application that loads and returns or re-encodes its pixels. This can disclose stale heap contents without memory corruption or a process crash. 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 >= 5.3.0, < 13.0.0)

[ Packages ]Affected open-source packages

• Pillow pipAffected >= 5.3.0, < 13.0.0 · fixed in 13.0.0 · GHSA-q45j-58j2-45rg

[ References ]References

• github.com/python-pillow/Pillow/commit/1d4773e6cea0c4a2814e6d4cdc099bbcf56da6ce
• github.com/python-pillow/Pillow/releases/tag/13.0.0
• github.com/python-pillow/Pillow/security/advisories/GHSA-q45j-58j2-45rg