Bug 2570449 (CVE-2026-125209)

Summary: CVE-2026-125209 ffmpeg: heap buffer overflow via DVD subtitle encoder
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: bbrownin
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in FFmpeg. A heap buffer overflow can occur in the DVD subtitle encoder when transcoding a media file containing crafted bitmap subtitles due to underestimating the RLE (Run-Length Encoding) output size for odd-width rectangles. This vulnerability can lead to memory corruption, potentially resulting in an application crash or arbitrary code execution.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2573440, 2573441, 2573442, 2573443, 2573444, 2573445, 2573446, 2573447    
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Description OSIDB Bzimport 2026-11-10 19:59:12 UTC
FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a heap buffer overflow vulnerability in the DVD subtitle encoder that underestimates RLE output size for odd-width rectangles. Attackers can supply files with crafted bitmap subtitles that, when transcoded to the dvdsub encoder, write past the output buffer and corrupt heap memory.