CVE-2026-77219

Name of the Vulnerable Software and Affected Versions GNU Emacs versions prior to 31.0.91

Description An integer overflow exists in the PBM/PPM/PGM image loader. This occurs because the loader uses signed integer arithmetic to multiply image dimensions and channel count. When provided with a crafted image featuring large dimensions and an elevated max color index, the result can wrap to a negative number. This bypasses bounds checks, causing the pixel reader to access heap memory beyond the allocated buffer. The leaked heap memory contents are then interpreted as pixel color values and rendered on screen.

Recommendations Update GNU Emacs to version 31.0.91 or later.