Bug 2570551 (CVE-2026-125246)

Summary: CVE-2026-125246 ffmpeg: ffmpeg: Denial of Service via assertion failure in cbs_jpeg_assemble_fragment
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. This flaw allows an attacker to cause a Denial of Service (DoS) by supplying a crafted JPEG or Motion JPEG (MJPEG) media stream. When the stream is processed, incorrect handling of stuffing bytes in the scan header triggers an internal assertion failure, causing the application to crash.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-11-10 20:06:29 UTC
FFmpeg through 9.0.2 contains a denial of service vulnerability in cbs_jpeg_assemble_fragment() that miscounts 0xff stuffing bytes in JPEG scan headers. Attackers can supply a crafted JPEG/MJPEG stream with 0xff in the scan header, triggering an av_assert0 abort when CBS-based bitstream filters process it.