{"id":"CVE-2026-125257","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-125257","summary":"FFmpeg through 9.0.2 contains an off-by-one heap overflow vulnerability in get_exponent_dynamic() in libavcodec/nellymoserenc.c that allows writing one element past the opt and path…","details":"FFmpeg through 9.0.2 contains an off-by-one heap overflow vulnerability in get_exponent_dynamic() in libavcodec/nellymoserenc.c that allows writing one element past the opt and path allocations. Attackers can supply crafted audio to applications encoding Nellymoser with trellis enabled, causing idx to equal OPT_SIZE and overwrite adjacent heap memory.","published":"2026-11-09T20:18:11.930","modified":"2026-11-09T20:18:11.930","cvss":{"score":7,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/FFmpeg/FFmpeg/commit/733bec3e19759520ccdbeb6c3c0cae280bbe6dc5","label":"FFmpeg/FFmpeg@733bec3"},"references":[{"type":"WEB","url":"https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24471"},{"type":"WEB","url":"https://github.com/FFmpeg/FFmpeg"},{"type":"WEB","url":"https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/nellymoserenc.c#L262"},{"type":"WEB","url":"https://github.com/FFmpeg/FFmpeg/commit/733bec3e19759520ccdbeb6c3c0cae280bbe6dc5"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-overflow-via-nellymoser-encoder-trellis-search"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-11-09T20:18:11.930"}}