CVE-2026-125197mediumCWE-191

CVE-2026-125197: medium-severity vulnerability in FFmpeg

FFmpeg through 9.0.2 Heap Out-of-Bounds Read via LCL/ZLIB Multithread Decoding

Published

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10Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.9
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.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
FFmpeg · FFmpeg
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