High [CVE-2026-66036] Arbitrary code execution via crafted video in vf_hqdn3d filter

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. A flaw was found in FFmpeg.

A remote attacker can exploit a heap out-of-bounds write vulnerability within the `vf_hqdn3d` filter by providing a specially crafted video file. This can result in arbitrary code execution or a denial of service.

Red Hat severity: Important — CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Weakness: CWE-787.

Affected Red Hat products: Red Hat Enterprise Linux AI 3.0 for RHEL 9; Red Hat Enterprise Linux AI 3.3 for RHEL 9; Red Hat Enterprise Linux AI 3.4 for RHEL 9; Red Hat Enterprise Linux AI 3.5 for RHEL 9; Red Hat Enterprise Linux AI 3.6 for RHEL 9; Red Hat OpenShift AI 2.25; Red Hat OpenShift AI 3.3; Red Hat OpenShift AI 3.5; Red Hat Enterprise Linux AI (RHEL AI) 3.