Bug 2555574 (CVE-2026-112257)

Summary: CVE-2026-112257 gimp: gimp: heap out-of-bounds read/write in PSD thumbnail loader (load_resource_1033)
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
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 GIMP. The PSD thumbnail resource loader performs a BGR-to-RGB channel swap with a fixed 3-byte stride and does not verify that the JPEG thumbnail is RGB. A crafted grayscale PSD thumbnail can cause a heap out-of-bounds read and write in the plug-in process, leading to a crash and potentially arbitrary code execution when the victim browses or opens the file.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2555575, 2555576    
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Description OSIDB Bzimport 2026-10-19 13:33:55 UTC 
A flaw was found in the GIMP PSD plug-in thumbnail loader. When a PSD embeds a grayscale JPEG thumbnail, the BGR-to-RGB swap in load_resource_1033() uses a hard-coded 3-byte stride without checking the JPEG component count, reading and writing past the heap buffer. The overflow length is controlled by the file. This can be triggered during thumbnail generation in the file chooser, without fully opening the image. This is distinct from CVE-2026-92248 (thumbnail allocation integer overflow).