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
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.
CVSS Scores
EPSS Scores
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Meta Information
Helpful Resources
Exploitability
| 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. |