Bug 2570243 (CVE-2026-125266)

Summary: CVE-2026-125266 ffmpeg: ffmpeg: Information disclosure via uninitialized stack memory in SANM decoder
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: bbrownin
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in FFmpeg. An attacker could exploit this vulnerability by enticing a user or automated system into processing a specially crafted SANM animation file. Due to the decoder reading uninitialized stack memory, sensitive memory contents from the decoding process can be exposed in the output video frames, leading to information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-10 19:45:31 UTC
FFmpeg through 9.0.2 contains an uninitialized stack memory disclosure vulnerability in old_codec23() of libavcodec/sanm.c that leaks stack bytes into decoded frames. Attackers can supply a crafted LucasArts SMUSH/SANM animation using codec 23 with an inline table to expose decoder process stack memory in output video.