CVE-2026-21508 Windows Storage Elevation of Privilege Vulnerability

High 7.0 Published Updated

An authorized local attacker can exploit improper authentication in Windows Storage 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-2026-21508?

CVE-2026-21508 is a high-severity vulnerability in Microsoft Windows 10 1607, published on 10 Feb 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Improper authentication in Windows Storage allows an authorized attacker to elevate privileges locally.

Weakness: CWE-426, CWE-287

Which versions are affected by CVE-2026-21508?

It affects 13 products.

Products include Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows 10 21h2, Microsoft Windows 10 22h2, Microsoft Windows 11 23h2, Microsoft Windows 11 24h2 and 7 more.

How do I fix CVE-2026-21508?

No fix has been published for CVE-2026-21508 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-21508 being exploited?

There is no known exploitation of CVE-2026-21508 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

All Microsoft Windows 10 1607 vulnerabilities

Sources

Also known as GHSA-2jrc-w4rc-f5cv.

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