CVE-2026-69809 Windows Active Directory Domain Services Denial of Service Vulnerability

High 7.5 Published 8 Sep 2026 Updated 14 Oct 2026

An unauthorized attacker can cause a denial of service in Windows Active Directory Domain Services due to a memory leak.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-69809?

CVE-2026-69809 is a high-severity denial of service vulnerability in Microsoft Windows 11 23h2, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Missing release of memory after effective lifetime in Active Directory Domain Services allows an unauthorized attacker to deny service over a network.

Weakness: CWE-401

Which versions are affected by CVE-2026-69809?

It affects 6 products.

Products include Microsoft Windows 11 23h2, Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1, Microsoft Windows Server 2022, Microsoft Windows Server 2025.

How do I fix CVE-2026-69809?

No fix has been published for CVE-2026-69809 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-69809 being exploited?

There is no known exploitation of CVE-2026-69809 in the wild and no public exploit code.

All Microsoft Windows 11 23h2 vulnerabilities

Sources

Also known as GHSA-6x59-3qf7-4cx8.