High [CVE-2026-78465] Gimp: integer overflow in pcx loader (planes=4) leads to heap overflow on 32-bit
This high-severity Red Hat Linux advisory covers CVE-2026-78465 affecting Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
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.
To exploit this vulnerability, an attacker needs to convince a user to process a specially crafted PCX image with GIMP, reducing the likelihood of exploitation. However, successful exploitation may potentially lead to arbitrary code execution or a denial of service.
Default Red Hat Enterprise Linux security features, including SELinux enforcement, Address Space Layout Randomization (ASLR) and NX (No-Execute) stack protection, significantly increase the difficulty of achieving arbitrary code execution, limiting the impact of this vulnerability. Due to this reason, this flaw has been rated with an important severity.
Red Hat severity: Important — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H).
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 3 hours ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 3 hours ago·verify at source
Mitigation checklist
- To mitigate this vulnerability, do not open PCX files from untrusted sources with GIMP.
Official advisory · high-confidence parse· fetched 3 hours ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.