CVE-2026-78465

Description

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.

Weakness classification

• CWE-190: Integer Overflow or Wraparound

Primary references

• secalert@redhat.com — Vendor Advisory
• secalert@redhat.com — Issue Tracking, Vendor Advisory
• secalert@redhat.com — Issue Tracking, Vendor Advisory, Exploit, Mitigation
• 134c704f-9b21-4f2e-91b3-4a467353bcc0 — Issue Tracking, Vendor Advisory, Exploit, Mitigation