CVE-2026-40369 Windows Kernel Elevation of Privilege Vulnerability
A heap-based buffer overflow in the Windows Kernel allows an authorized local attacker to elevate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-40369?
CVE-2026-40369 is a high-severity memory corruption vulnerability in Microsoft Windows 11 24h2, published on 12 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.
Weakness: CWE-822
Which versions are affected by CVE-2026-40369?
It affects 4 products.
Products include Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1, Microsoft Windows Server 2025.
How do I fix CVE-2026-40369?
No fix has been published for CVE-2026-40369 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-40369 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40369 exists.
Public exploit code: 7 proofs of concept on GitHub.
Other vulnerabilities in Microsoft Windows 11 24h2
- CVE-2025-60710 Microsoft Windows Link Following
- CVE-2026-54990 Remote Desktop Client Remote Code Execution Vulnerability
- CVE-2025-50165 Windows Graphics Component Remote Code Execution Vulnerability
- CVE-2025-21311 Windows NTLM V1 Elevation of Privilege Vulnerability
- CVE-2026-108463 Windows SmartScreen Security Feature Bypass Vulnerability
Sources
Also known as GHSA-4qhv-qjg6-r699.