CVE-2026-83499: Windows Server Update Service Elevation of Privilege Vulnerability
Insufficient granularity of access control in Windows Server Update Service allows an authorized attacker to elevate privileges locally.
Other sources
Windows Server Update Service Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.3.9600.23470Patch KB5126836 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.2.9200.26434Patch KB5126835 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.14393.9612Patch KB5126868 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.9376Patch KB5126651 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33650Patch KB5126646
Event History
Frequently Asked Questions
Which environments should be prioritized for review?
Review systems running Microsoft Windows 10 or Windows Server 2012, 2012 R2, 2016, 2019, 2022, or 2025, particularly where Windows Server Update Service is deployed.
What access does an attacker need to exploit this issue?
The attacker must already have authorized local access with low privileges. The CVSS vector indicates no user interaction is required.
What could a successful exploit allow?
The CVSS metrics rate confidentiality, integrity, and availability impact as high, indicating that successful local privilege elevation could have broad impact on the affected system.