Vulnerability · Published Aug 11, 2026 · Assigned by microsoft
CVE-2026-66804Microsoft Windows Cross Device Service Elevation of Privilege Vulnerability
High 7.8
In plain English
A high-severity improper access control in Windows 10 Version 22H2 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.3%top 77.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack tooling1Public PoC
Official description
Improper access control in Windows Cross Device Service allows an authorized attacker to elevate privileges locally.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 Version 22H2 | 10.0.19045.0 – before 10.0.19045.7663 |
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 – before 10.0.26100.9168 |
| Microsoft | Windows 11 Version 25H2 | 10.0.26200.0 – before 10.0.26200.9168 |
| Microsoft | Windows 11 version 26H1 | 10.0.28000.0 – before 10.0.28000.2704 |
Weakness: CWE-284 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
References
- Microsoft Windows Cross Device Service Elevation of Privilege Vulnerability vendor-advisory, patch