CVE-2026-125203

Publication date 10 November 2026

Last updated 12 November 2026


Ubuntu priority

Cvss 3 Severity Score

7.8 · High

Score breakdown

Description

FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a heap buffer overflow vulnerability in the Cook multichannel decoder in libavcodec/cook.c that fails to verify subpacket channel masks are disjoint. Attackers can supply a crafted RealMedia Cook stream with overlapping subpacket masks, causing cook_decode_frame() to write decoded samples beyond allocated output planes in any application decoding the file.

Status

Package Ubuntu Release Status
ffmpeg 26.10 stonking
Needs evaluation
26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty Not in release

Severity score breakdown

CVSS version:

Base score 8.5 · High

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Base score 7.8 · High

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H


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