Bug 2570441 (CVE-2026-125269)

Summary: CVE-2026-125269 ffmpeg: ffmpeg: Arbitrary code execution via crafted H.264 stream
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
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. A double free vulnerability exists in the video codec library when handling Supplemental Enhancement Information (SEI) metadata due to the reuse of stale memory references. By tricking a user or automated system into processing a specially crafted H.264 video stream, an attacker could trigger heap memory corruption, potentially leading to arbitrary code execution or a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-10 19:58:30 UTC 
FFmpeg through 9.0.2 contains a double free vulnerability in libavcodec/cbs_sei.c where cbs_sei_delete_message() leaves a stale extension_data reference that ff_cbs_sei_add_message() reuses. Attackers can supply a crafted H.264 stream with a display orientation SEI message followed by payload extension data, processed by h264_metadata with display_orientation=insert, to corrupt heap memory.