Bug 2569532 (CVE-2026-125098)

Summary: CVE-2026-125098 ffmpeg: ffmpeg: Information disclosure via malformed WebP alpha chunk
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 providing a specially crafted WebP image containing a truncated alpha (transparency) data chunk. Because the decoder fails to initialize memory for these incomplete chunks, processing the file can result in information disclosure by exposing stale pixel data from previously decoded frames.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-10 13:00:56 UTC
FFmpeg through 9.0.2 contains an information disclosure vulnerability in vp8_lossy_decode_alpha() in libavcodec/webp.c that leaves alpha plane memory uninitialized for short uncompressed ALPH chunks. Attackers can supply a crafted WebP image whose ALPH chunk is shorter than width * height to disclose stale pixel data from previously decoded frames.