CVE-2026-125197
Received Received - Intake

Integer Underflow in FFmpeg LCL Decoder

Vulnerability report for CVE-2026-125197, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-11-09

Last updated on: 2026-11-09

Assigner: VulnCheck

Description

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.

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Meta Information

Published
2026-11-09
Last Modified
2026-11-09
Generated
2026-11-09
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
FFmpeg FFmpeg From 0 (inc) to 9.0.2 (inc)

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-191 The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.

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