CVE WatchAug 10, 2026

CVE-2021-33771

Microsoft Windows Kernel Privilege Escalation Vulnerability

CVSS

7.8

High

EPSS

10.2%

p96

KEV

YES

Nov 3, 2021

Exploit Today

0-100

Published: Jul 14, 2021 · Last modified: Aug 10, 2026

EPSS · 30d

10.2%EPSS · 30 days10.2%

2026-09-172026-10-15

KEV catalog record

Product

Microsoft / Windows

Vulnerability

Microsoft Windows Kernel Privilege Escalation Vulnerability

Added to KEV

Nov 3, 2021

Remediate by

Nov 17, 2021

Known ransomware use

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

Technical description

Windows Kernel Elevation of Privilege Vulnerability

Official references

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