Bug 2524834 (CVE-2026-81893)

Summary: CVE-2026-81893 gdk-pixbuf: gdk-pixbuf: invalid write in JPEG ICC profile parser on error recovery
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in gdk-pixbuf. When loading a specially crafted JPEG image containing chunked ICC profile markers, an error during ICC profile parsing can leave stale size metadata after the profile buffer is freed. A subsequent allocation in the same decode can cause an out-of-bounds write, potentially crashing the application. To exploit this flaw, an application using gdk-pixbuf must process the malicious JPEG image. Affected version >= 2.26.4
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2525141, 2525142    
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Description OSIDB Bzimport 2026-08-27 06:08:58 UTC
A flaw was found in gdk-pixbuf's JPEG loader (io-jpeg.c). When parsing chunked ICC profile data from JPEG APP2 markers, the error cleanup path in jpeg_parse_exif_app2_segment() frees the ICC profile buffer but previously failed to reset icc_profile_size and icc_profile_size_allocated. A specially crafted JPEG can trigger allocation, an error that frees the buffer while leaving stale size metadata, and a subsequent re-allocation that leads to an out-of-bounds write during ICC profile assembly.

The issue was introduced when error cleanup was added for chunked ICC profile handling in gdk-pixbuf 2.43.4/2.44.0 (commit 4af78023). It is fixed upstream in commit efe658674bd103d1c9bf50809d5767a3f6dd5a01 ("jpeg: When freeing memory, unset the size"), merged via https://gitlab.gnome.org/GNOME/gdk-pixbuf/-/merge_requests/278 on 2026-08-24. No fixed upstream release tag exists yet.

Red Hat tracking: PSIRTSUPT-22558.