What’s Vulnerable › Vulnerabilities

CVE-2021-33744: Windows Secure Kernel Mode Security Feature Bypass Vulnerability

• Severity: high (CVSS 7.2 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-07-14 · updated 2026-08-10

Description

Windows Secure Kernel Mode Security Feature Bypass Vulnerability

Affected products

• Microsoft Windows 10 Version 1607: 20h2, 21h1, 1809, 1909, 2004
• Microsoft Windows Server 2016: 20h2, 2004
• Microsoft Windows Server 2019: all versions
• Microsoft Windows 10: from 10.0.17763.0 before 10.0.17763.2061 — fixed in 10.0.17763.2061
• Microsoft Windows 10 1909: from 10.0.0 before 10.0.18363.1679 — fixed in 10.0.18363.1679
• Microsoft Windows 10 2004: from 10.0.0 before 10.0.19041.1110 — fixed in 10.0.19041.1110
• Microsoft Windows 10 21H1: from 10.0.0 before 10.0.19043.1110 — fixed in 10.0.19043.1110
• Microsoft Windows Server 2019: from 10.0.17763.0 before 10.0.17763.2061 — fixed in 10.0.17763.2061
• Microsoft Windows Server version 2004: from 10.0.0 before 10.0.19041.1110 — fixed in 10.0.19041.1110
• Microsoft Windows Server version 20H2: from 10.0.0 before 10.0.19042.1110 — fixed in 10.0.19042.1110

How to fix

Upgrade to a fixed version: Microsoft Windows 10 10.0.17763.2061; Microsoft Windows 10 1909 10.0.18363.1679; Microsoft Windows 10 2004 10.0.19041.1110; Microsoft Windows 10 21H1 10.0.19043.1110; Microsoft Windows Server 2019 10.0.17763.2061; Microsoft Windows Server version 2004 10.0.19041.1110; Microsoft Windows Server version 20H2 10.0.19042.1110. Check the vendor advisory for mitigations.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33744
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33744

Get alerted when CVE-2021-33744 or the next vulnerability affects your stack