CVE-2026-66036 HIGH

CVE-2026-66036: FFmpeg Heap Out-of-Bounds Write in vf_hqdn3d Filter

Vendor Ffmpeg
Product FFmpeg
Weakness CWE-122
Published July 24, 2026
Last update July 24, 2026

CVSS base score

7.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

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

What the vulnerability does

01Description

FFmpeg through 8.1.2, fixed in commit 5d7112c, contains a heap out-of-bounds write vulnerability in the vf_hqdn3d filter that allows attackers to corrupt heap memory by supplying a crafted video whose frame resolution increases between frames when filtergraph reinitialization is disabled via the -reinit_filter 0 option. Attackers can provide a malicious video input where vf_hqdn3d.config_input() allocates undersized per-plane line-history buffers based on the initial frame width, and subsequent larger frames cause denoise_spatial() to write beyond the allocation boundary, resulting in heap memory corruption.

Key dates

02Disclosure timeline

July 24, 2026 CVE published