CVE-2021-33771
Microsoft Windows Kernel Privilege Escalation Vulnerability
CVSS
7.8
High
EPSS
10.2%
p95
KEV
YES
Nov 3, 2021
Exploit Today
79
0-100
Published: Jul 14, 2021 · Last modified: Aug 10, 2026
6.3%EPSS · 30 days10.2%
2026-08-022026-08-31
Product
Microsoft / Windows
Vulnerability
Microsoft Windows Kernel Privilege Escalation Vulnerability
Added to KEV
Nov 3, 2021
Remediate by
Nov 17, 2021
Known ransomware use
No
Summary description
Microsoft Windows kernel contains an unspecified vulnerability that allows for privilege escalation.
Required action
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-33771
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