Description
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.
Affected products
ffmpeg: ffmpeg
References5
- code.ffmpeg.org/FFmpeg/FFmpeg/commit/1006a2151236f9235bf02822f2… Patch
- code.ffmpeg.org/FFmpeg/FFmpeg/commit/16b2049d4d5222db6cd7c03140… Patch
- code.ffmpeg.org/FFmpeg/FFmpeg/commit/db05df9d135fb56a4babb836d5… Patch
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23898 Issue TrackingPatch
- www.vulncheck.com/advisories/ffmpeg-heap-out-of-bounds-write-in… PatchThird Party Advisory
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 4.0
-
8.5
HIGH
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 14 · as of 12 November 2026
- CWE
- CWE-787
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.