CVE-2021-26866
HighCVSS 7.1Exploitation Probability (EPSS)
Elevated risk63th percentile - higher than 63% of all known CVEs
Summary
Elevation of privilege vulnerability in Windows Update Service. Allows an attacker to gain higher privileges on the system.
Risk Assessment
Risk of privilege escalation and full system compromise.
Recommendation
Apply security patches for Windows Update Service.
Other vulnerabilities in Windows Update Service
See all- CVE-2026-70142High
Untrusted search path in Windows Update Service. An authorized attacker can exploit this to elevate privileges locally.
- CVE-2026-70139High
Heap-based buffer overflow in Windows Update Service. An authorized attacker can exploit this to elevate privileges locally.
- CVE-2026-70056High
A use after free vulnerability exists in the Windows Update Service. An authorized attacker can exploit this flaw to elevate privileges locally.
- CVE-2026-100203High
Heap-based buffer overflow in Windows Update Service allows an authorized attacker to elevate privileges locally.
- CVE-2026-100200High
A use-after-free vulnerability in the Windows Update Service allows an authorized attacker to elevate privileges locally. The flaw resides in the system component responsible for updates.
Original NVD description (English source)
Windows Update Service Elevation of Privilege Vulnerability
Vulnerability data from NVD (NIST) · CISA KEV · EPSS