Bug 2569621 (CVE-2026-125191)

Summary: CVE-2026-125191 ffmpeg: ffmpeg: Denial of Service via reference count leak in V4L2 decoder
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 reference count leak within the Video4Linux2 (V4L2) decoder can trigger a deadlock when processing multi-plane video formats. By supplying a specially crafted video stream featuring dynamic resolution changes, an attacker can cause the decoding process to hang indefinitely. This failure leaves the host application unresponsive, resulting in 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 13:15:58 UTC
FFmpeg through 9.0.2 contains a reference count leak in libavcodec/v4l2_buffers.c that allows attackers to deadlock the V4L2 mem2mem decoder on multi-plane capture formats. Attackers can supply crafted H.264, HEVC, or VP9 streams with resolution changes, making ff_v4l2_m2m_codec_reinit() wait forever and hang the decoding application.