CVE-2026-84011 Windows SMB Client Security Feature Bypass Vulnerability

Medium 5.5 Published 13 Oct 2026 Updated 29 Oct 2026

An authorized local attacker can bypass security features in the Windows SMB Client due to incorrect authorization checks.

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-2026-84011?

CVE-2026-84011 is a medium-severity vulnerability in Microsoft Windows 11 23h2, published on 13 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Incorrect authorization in Windows SMB Client allows an authorized attacker to bypass a security feature locally.

Weakness: CWE-863

Which versions are affected by CVE-2026-84011?

It affects 7 products.

Products include Microsoft Windows 11 23h2, Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1, Microsoft Windows 11 26h2, Microsoft Windows Server 2022 and 1 more.

How do I fix CVE-2026-84011?

No fix has been published for CVE-2026-84011 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-84011 being exploited?

There is no known exploitation of CVE-2026-84011 in the wild and no public exploit code.

All Microsoft Windows 11 23h2 vulnerabilities

Sources

Also known as GHSA-vpw4-8hvr-46cq.