Out-of-Bounds Write Vulnerability in Pillow Imaging Library by Python
CVE-2026-96639
9.8CRITICAL
What is CVE-2026-96639?
The Pillow imaging library, utilized for Python, has a vulnerability that arises from improper handling of multi-frame loaders. Specifically, when transitioning between narrow frame modes and wider color modes (such as RGB or CMYK), it can incorrectly retain memory allocations for previous frames. This flaw allows crafted image files, including PSD, MPO, and others, to exploit the outdated native storage, leading to potential out-of-bounds writes or crashes. Additionally, certain path transitions may enable native over-reads or even command execution in specific runtime scenarios. The issue has been addressed in version 13.0.0 of Pillow.
Affected Version(s)
Pillow >= 11.0.0, < 13.0.0