Vulnerability in Microsoft Windows 10 Version 22h2
CVE-2026-66804
Improper access control in Windows Cross Device Service allows an authorized attacker to elevate privileges locally.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Microsoft Windows 10 Version 22h2 — versions 10.0.19045.0
- Microsoft Windows 11 Version 24h2 — versions 10.0.26100.0
- Microsoft Windows 11 Version 25h2 — versions 10.0.26200.0
- Microsoft Windows 11 Version 26h1 — versions 10.0.28000.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- secure@microsoft.com (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-66804?
- CVE-2026-66804 is a high-severity vulnerability in Microsoft Windows 10 Version 22h2, classified under Improper Access Control. CVSS score: 7.8/10. Published 2026-08-11.
- How severe is CVE-2026-66804?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2026-66804 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.