{"id":"CVE-2026-125256","title":"FFmpeg through 9.0.2 Heap Buffer Overflow via RISC-V Vector diff_bytes Routine","summary":"FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in ff_llvidenc_diff_bytes_rvv() that allows attackers to corrupt heap memory by triggering negative length values in the Huffyuv encoder. Attackers can supply RGB video n…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","cvssSource":"cna","cwe":["CWE-787"],"vendor":"FFmpeg","product":"FFmpeg","affected":["FFmpeg >= 7.0 <= 9.0.2"],"published":"2026-11-09","updated":"2026-11-09","sourceUpdated":"2026-11-09T19:12:00.407Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-125256","references":[{"url":"https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25573"},{"url":"https://github.com/FFmpeg/FFmpeg/commit/1f7bdea654a8a9a1761759e22d83943371cff21f","label":"Patch Commit"},{"url":"https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/riscv/llvidencdsp_rvv.S#L26"},{"url":"https://github.com/FFmpeg/FFmpeg"},{"url":"https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-buffer-overflow-via-risc-v-vector-diff-bytes-routine","label":"VulnCheck Advisory: FFmpeg through 9.0.2 Heap Buffer Overflow via RISC-V Vector diff_bytes Routine"}],"tags":["cve.org"],"ingestedAt":"2026-11-09T20:27:27.084Z","slug":"CVE-2026-125256","body":"## Overview\n\nFFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in ff_llvidenc_diff_bytes_rvv() that allows attackers to corrupt heap memory by triggering negative length values in the Huffyuv encoder. Attackers can supply RGB video narrower than 8 or 16 pixels for huffyuv transcoding on RVV-enabled RISC-V builds, causing writes past the encoder's temp buffer.\n\n## Affected\n\n- `FFmpeg >= 7.0 <= 9.0.2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}