CVE-2026-125256

high

Description

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 narrower than 8 or 16 pixels for huffyuv transcoding on RVV-enabled RISC-V builds, causing writes past the encoder's temp buffer.

References

https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-buffer-overflow-via-risc-v-vector-diff-bytes-routine

https://github.com/FFmpeg/FFmpeg/commit/1f7bdea654a8a9a1761759e22d83943371cff21f

https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/riscv/llvidencdsp_rvv.S#L26

https://github.com/FFmpeg/FFmpeg

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-120206

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25573

Details

Source: Mitre, NVD

Published: 2026-11-09

Updated: 2026-11-10

Risk Information

CVSS v2

Base Score: 6.2

Vector: CVSS2#AV:L/AC:H/Au:N/C:C/I:C/A:C

Severity: Medium

CVSS v3

Base Score: 7

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

Severity: High

CVSS v4

Base Score: 7.3

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

Severity: High

EPSS

EPSS: 0.00143