{"id":"CVE-2026-125203","published":"2026-11-09T19:16:56.740","lastModified":"2026-11-10T21:46:37.837","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.","cvssScore":7.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cwes":["CWE-787"],"vendors":[],"products":[],"references":[{"url":"https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24485","tags":[]},{"url":"https://github.com/FFmpeg/FFmpeg","tags":[]},{"url":"https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/cook.c#L1294","tags":[]},{"url":"https://github.com/FFmpeg/FFmpeg/commit/3e09f5e24eb277a6d011745ff03e602f61c5c171","tags":[]},{"url":"https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-heap-buffer-overflow-in-cook-multichannel-decoder","tags":[]}],"exploitRefs":[{"url":"https://github.com/FFmpeg/FFmpeg","tags":[]},{"url":"https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/cook.c#L1294","tags":[]},{"url":"https://github.com/FFmpeg/FFmpeg/commit/3e09f5e24eb277a6d011745ff03e602f61c5c171","tags":[]}],"hasPoc":true,"ai":null}