CVE-2021-40450VulnerabilityPublished 04/25/2022Updated 10/24/2026

CVE-2021-40450: Microsoft Win32k Privilege Escalation Vulnerability

Affects Microsoft Win32kSource CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 04/25/2022
KEV deadline: 05/16/2022
EPSS: 1.6% chance of exploitation in 30 days – higher than 75% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2021-40450 (opens in a new tab)

Description

CVE-2021-40450 is a high-severity privilege escalation vulnerability in Microsoft Win32k. It allows an attacker to elevate privileges on an affected system. The vulnerability has been exploited in the wild. No specific affected versions or patch information is provided in the available data.

Summary

Microsoft Win32k contains an unspecified vulnerability identified as CVE-2021-40450 that enables privilege escalation. This vulnerability has been observed being exploited in the wild, indicating active threat usage. Details on the exact nature of the flaw, affected versions, and remediation are not provided in the available information.

Impact

Successful exploitation of this vulnerability allows an attacker to escalate privileges on a compromised system, potentially gaining higher-level access than initially permitted. This can lead to further system compromise or unauthorized actions.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Due to the lack of explicit patch or mitigation information, organizations should monitor official Microsoft security advisories for updates and apply any released fixes promptly.

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 11:27:16 UTC

References

Related threats