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.
Affected products
gimp: gimp
References4
- access.redhat.com/security/cve/CVE-2026-78465 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2522057 Issue TrackingVendor Advisory
- gitlab.gnome.org/GNOME/gimp/-/work_items/16578 ExploitIssue TrackingMitigationVendor Advisory
- gitlab.gnome.org/GNOME/gimp/-/work_items/16578 ExploitIssue TrackingMitigationVendor Advisory
Metrics
- CVSS 3.1
-
7.0
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 21 · as of 9 November 2026
- CWE
- CWE-190
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