Bug 2496576 (CVE-2026-59087)

Summary:	CVE-2026-59087 gimp: Heap buffer overflow in `file-seattle-filmworks` load — `fread` writes attacker-controlled length into undersized allocation
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the GIMP image manipulation program, specifically within its Seattle Filmworks file loader. A remote attacker could exploit this vulnerability by tricking a user into opening a specially crafted Seattle Filmworks file. This could lead to a heap overflow, allowing the attacker to write several kilobytes of controlled data beyond the intended memory buffer. Such an overflow can result in memory corruption, potentially leading to arbitrary code execution or a denial of service.	Story Points:	---
Clone Of:		Environment:
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Documentation:	---	CRM:
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2513088
Bug Blocks:

Description OSIDB Bzimport 2026-07-02 15:16:12 UTC

The Seattle Filmworks file loader reads two file-position-derived values, index and metadata_len[1], uses only metadata_len[1] to size the allocation for photo_date, then freads index - metadata_len[1] bytes into it. Both values are attacker-controlled and independent. When index ≫ metadata_len[1], the read overflows the heap by up to several KB of attacker-controlled bytes.
In a build with _FORTIFY_SOURCE (Ubuntu default), glibc detects this at runtime and aborts. In a non-FORTIFY build the corruption is silent.

Issue Link: https://gitlab.gnome.org/GNOME/gimp/-/work_items/16491