CVE-2026-66036: Ffmpeg

High severity, CVSS 8.8. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• Ffmpeg Ffmpeg: up to and including 8.1.2

Published 2026-07-24. Last modified 2026-08-07.