FFmpeg versions from 4.4 up to, but not including, 9.0 contain an out-of-bounds heap write vulnerability in the native GoPro CineForm HD (CFHD) decoder that allows remote attackers to corrupt heap memory by supplying a crafted AVI file during stream probing. The cfhd_decode() function fails to enforce the non-Bayer logical output-width invariant in the transform-type-2 reconstruction path, causing horiz_filter_clip() to write oversized 16-bit sample rows far beyond the allocated output frame buffer, which can be escalated to arbitrary code execution via overwrite of a live cleanup callback pointer.
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23898
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/db05df9d135fb56a4babb836d5e9f5c1d984e087
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/16b2049d4d5222db6cd7c031409058571c94f6a9
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/1006a2151236f9235bf02822f263b3fb0532111e
Published: 2026-08-06
Updated: 2026-08-07
Base Score: 7.2
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.5
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
Severity: High
EPSS: 0.00209