Bug 2570762 (CVE-2026-125197)

Summary: CVE-2026-125197 ffmpeg: ffmpeg: Denial of Service via integer underflow in LCL 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. An attacker could exploit an integer underflow in the Lossless Codec Library (LCL) video decoder by supplying a specially crafted media file containing malformed video packets. When processed, this flaw triggers a heap out-of-bounds read that primarily causes the decoding application to crash, resulting in a Denial of Service (DoS), and may potentially expose sensitive memory contents.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-10 20:20:25 UTC
FFmpeg through 9.0.2 contains an integer underflow in decode_frame() in libavcodec/lcldec.c that allows attackers to trigger a heap out-of-bounds read via short ZLIB packets with FLAG_MULTITHREAD. Attackers can supply a crafted AVI or MKV file with an LCL video stream whose packet is shorter than 8 bytes, bypassing length clamping to crash the decoding application.