Improper access control in Microsoft Windows - CVE-2026-66804

 

Improper access control in Microsoft Windows - CVE-2026-66804

Published: August 12, 2026


Vulnerability identifier: #VU141866
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-66804
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to elevate privileges.

The vulnerability exists due to improper access control in Windows Cross Device Service when handling local access to the service. A local user can exploit the access control weakness to elevate privileges.

Successful exploitation could result in SYSTEM privileges.


Affected software

Microsoft Windows

How to mitigate CVE-2026-66804

Install security update from vendor's website.

Microsoft Windows - addressed in versions 10 22H2 10.0.19045.7663, 11 24H2 10.0.26100.9106, 11 24H2 10.0.26100.9168, 11 25H2 10.0.26200.9168, 11 26H1 10.0.28000.2704

External References

Related Security Bulletins