Bug 2459992 (CVE-2026-6861)

Summary: CVE-2026-6861 emacs: Emacs: Memory corruption vulnerability when processing SVG CSS
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in GNU Emacs. This vulnerability, a memory corruption issue, occurs when Emacs processes specially crafted SVG (Scalable Vector Graphics) CSS (Cascading Style Sheets) data. A local user could exploit this by convincing a victim to open a malicious SVG file, which may lead to a denial of service (DoS) or potentially information disclosure.
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Bug Depends On: 2460584, 2460585, 2460586    
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Description OSIDB Bzimport 2026-04-21 07:35:33 UTC
Off-by-one heap buffer overflow and uninitialized heap read in GNU Emacs src/image.c svg_load_image() when processing SVG CSS. The null terminator is written one byte past the allocation. Affected: Emacs 28.1 through 30.2. Fixed upstream on emacs-30: commit 8f535370b9.

Public bug: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=80851