CVE-2021-34484: Microsoft Windows User Profile Service Privilege Escalation Vulnerability

High severity, CVSS 7.8. Actively exploited: in CISA KEV since 2022-03-31. EPSS: 21.8% chance of exploitation in the next 30 days.

Windows User Profile Service Elevation of Privilege Vulnerability

Affected products

• Microsoft Windows 10 1507: before 10.0.10240.19022 (fixed in 10.0.10240.19022)
• Microsoft Windows 10 1607: before 10.0.14393.4583 (fixed in 10.0.14393.4583)
• Microsoft Windows 10 1809: before 10.0.17763.2114 (fixed in 10.0.17763.2114)
• Microsoft Windows 10 1909: before 10.0.18363.1734 (fixed in 10.0.18363.1734)
• Microsoft Windows 10 2004: before 10.0.19041.1165 (fixed in 10.0.19041.1165)
• Microsoft Windows 10 20h2: before 10.0.19042.1165 (fixed in 10.0.19042.1165)
• Microsoft Windows 10 21h1: before 10.0.19043.1165 (fixed in 10.0.19043.1165)
• Microsoft Windows 7: affected versions not specified
• Microsoft Windows 8.1: affected versions not specified
• Microsoft Windows Rt 8.1: affected versions not specified
• Microsoft Windows Server 2004: before 10.0.19041.1165 (fixed in 10.0.19041.1165)
• Microsoft Windows Server 2008: affected versions not specified; version r2 only
• Microsoft Windows Server 2012: affected versions not specified; version r2 only
• Microsoft Windows Server 2016: before 10.0.14393.4583 (fixed in 10.0.14393.4583)
• Microsoft Windows Server 2019: before 10.0.17763.2114 (fixed in 10.0.17763.2114)
• Microsoft Windows Server 20h2: before 10.0.19042.1165 (fixed in 10.0.19042.1165)

Published 2021-08-12. Last modified 2026-08-10.