Red Hat file-pcx plugin: integer overflow

High7.0CVE-2026-78465 · Published Aug 24, 2026 · updated Sep 1, 2026

A flaw was found in the file-pcx plugin in GIMP, affecting 32-bit builds only. When processing a PCX image file, the plugin calculates memory allocation sizes based on the image dimensions and the number of color planes. If a crafted file sets the number of planes to 4 alongside sufficiently large dimensions, the calculation exceeds the 32-bit integer limit and overflows, resulting in an undersized heap-based buffer allocation. This integer overflow issue results in a heap-based buffer overflow when the plugin subsequently writes image data into the undersized buffer, causing memory corruption, potentially leading to arbitrary code execution or a denial of service.