CVE-2021-40450: Microsoft Win32k Privilege Escalation Vulnerability
CVE-2021-40450 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2022-04-25
Microsoft Win32k contains an elevation of privilege vulnerability that allows a local attacker to gain system-level privileges. The flaw is caused by insufficient restrictions within the Win32k kernel-mode driver. This vulnerability has been observed being exploited in the wild.
Yes. CVE-2021-40450 is known to be exploited in the wild, first recorded on 25 April 2022. Treat it as urgent.
How severe is CVE-2021-40450?
Critical severity, with a CVSS score of 7.8, published 25 April 2022.
Which products and versions are affected?
Microsoft Windows 10 1809, 1909, 2004, 20H2, 21H1; Microsoft Windows 11 21H2; Microsoft Windows Server 2004, 20H2, 2019, 2022.
Is there a fix for CVE-2021-40450?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2021-40450 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2021-40450?
Check whether you run Microsoft Win32K. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Affected products
Microsoft Windows 10 1809, 1909, 2004, 20H2, 21H1
Microsoft Windows 11 21H2
Microsoft Windows Server 2004, 20H2, 2019, 2022
Timeline
2021-10-19: disclosed: Initial analysis by NIST and Microsoft advisory release
2022-04-25: kev added: Added to CISA's Known Exploited Vulnerabilities Catalog