Description
A flaw was found in the file-icns plugin in GIMP. When applying a decompressed mask during ICNS image processing, the plugin reads from the mask data buffer without verifying if the cursor exceeds the allocated resource size. If a crafted file contains a truncated mask resource, the icns_decompress function continues reading past the bounds of the buffer. This out-of-bounds read vulnerability results in information disclosure of heap contents, where memory contents are leaked as alpha channel pixel values, or a crash leading to a denial of service if unmapped memory is accessed.
Affected products
gimp: gimp; redhat: enterprise linux
References5
- access.redhat.com/security/cve/CVE-2026-66759 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2507557 Issue TrackingVendor Advisory
- gitlab.gnome.org/GNOME/gimp/-/issues/16528 ExploitIssue TrackingVendor Advisory
- gitlab.gnome.org/GNOME/gimp/-/issues/16528 ExploitIssue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:50817 Issue Tracking
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 24 · as of 13 November 2026
- CWE
- CWE-125
Could this be exploited in your environment?
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