CVE-2026-20804 Windows Hello Tampering Vulnerability

High 7.7 Published Updated

An unauthorized local attacker can exploit incorrect privilege assignment in Windows Hello to perform tampering, requiring a security patch.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Local or same network only
Victim action needed
Not needed
Fix
None listed

What is CVE-2026-20804?

CVE-2026-20804 is a high-severity vulnerability in Microsoft Windows 10 1607, published on 13 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Incorrect privilege assignment in Windows Hello allows an unauthorized attacker to perform tampering locally.

Weakness: CWE-266

Which versions are affected by CVE-2026-20804?

It affects 12 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 6 more.

How do I fix CVE-2026-20804?

No fix has been published for CVE-2026-20804 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-20804 being exploited?

There is no known exploitation of CVE-2026-20804 in the wild and no public exploit code.

All Microsoft Windows 10 1607 vulnerabilities

Sources

Also known as GHSA-7mcr-xx2r-qf84.

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