Libav: 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… (CVE-2026-66036)
FFmpeg versions through 8.1.2 contain a heap out-of-bounds write vulnerability in the vf_hqdn3d filter. This flaw occurs when a crafted video input has increasing frame resolution between frames while filtergraph reinitialization is disabled (-reinit_filter 0). The vulnerability allows heap memory corruption due to undersized buffer allocation for line-history, leading to out-of-bounds writes during denoising operations.
AI Analysis
Technical Summary
The vulnerability in FFmpeg (libav) up to version 8.1.2 is a heap out-of-bounds write in the vf_hqdn3d filter. When the filtergraph reinitialization is disabled via the -reinit_filter 0 option, and a crafted video input has frames with increasing resolution, the function vf_hqdn3d.config_input() allocates line-history buffers based on the initial frame width. Subsequent larger frames cause denoise_spatial() to write beyond these buffers, corrupting heap memory. This issue is tracked as CVE-2026-66036 and was fixed in commit 5d7112c.
Potential Impact
Successful exploitation can lead to heap memory corruption, potentially causing denial of service or arbitrary code execution. The CVSS 3.1 base score is 8.8, indicating high severity with network attack vector, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A fix for this vulnerability is available in commit 5d7112c. Users should upgrade to a version of FFmpeg that includes this commit or later. Until patched, avoid using the vf_hqdn3d filter with the -reinit_filter 0 option on untrusted video inputs to mitigate risk. Patch status is not explicitly confirmed in vendor advisories here; verify with official FFmpeg sources for the fixed version.
Libav: 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… (CVE-2026-66036)
Description
FFmpeg versions through 8.1.2 contain a heap out-of-bounds write vulnerability in the vf_hqdn3d filter. This flaw occurs when a crafted video input has increasing frame resolution between frames while filtergraph reinitialization is disabled (-reinit_filter 0). The vulnerability allows heap memory corruption due to undersized buffer allocation for line-history, leading to out-of-bounds writes during denoising operations.
CVSS v3.1
Score 8.8high
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in FFmpeg (libav) up to version 8.1.2 is a heap out-of-bounds write in the vf_hqdn3d filter. When the filtergraph reinitialization is disabled via the -reinit_filter 0 option, and a crafted video input has frames with increasing resolution, the function vf_hqdn3d.config_input() allocates line-history buffers based on the initial frame width. Subsequent larger frames cause denoise_spatial() to write beyond these buffers, corrupting heap memory. This issue is tracked as CVE-2026-66036 and was fixed in commit 5d7112c.
Potential Impact
Successful exploitation can lead to heap memory corruption, potentially causing denial of service or arbitrary code execution. The CVSS 3.1 base score is 8.8, indicating high severity with network attack vector, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A fix for this vulnerability is available in commit 5d7112c. Users should upgrade to a version of FFmpeg that includes this commit or later. Until patched, avoid using the vf_hqdn3d filter with the -reinit_filter 0 option on untrusted video inputs to mitigate risk. Patch status is not explicitly confirmed in vendor advisories here; verify with official FFmpeg sources for the fixed version.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-575m-jfmw-q76c
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-66036"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a65422a9c2644c7f808a1a7
Added to database: 07/25/2026, 23:09:30 UTC
Last enriched: 08/08/2026, 16:58:34 UTC
Last updated: 09/07/2026, 22:52:14 UTC
Views: 60
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.