Threat Signal Report

Proof-of-Concept Code Now Available for an Exploited Windows Local Privilege Escalation Vulnerability

Description

FortiGuard Labs is aware that a Proof-of-Concept (POC) code for a newly patched Windows vulnerability (CVE-2022-21882) that is reported to have been exploited in the wild was released to a publicly available online repository. CVE-2022-21882 is a local privilege (LPE) escalation vulnerability which allows a local, authenticated attacker to gain elevated local system or administrator privileges through a vulnerability in the Win32k.sys driver. The vulnerability is rated as Important by Microsoft and has CVSS score of 7.0.

Why is this Significant?

This is significant because now that the POC for CVE-2022-21882 has become available to the public attacks leveraging the vulnerability will likely increase. Because CVE-2022-21882 is a local privilege escalation the vulnerability will be used by an attacker that already has access to the network or will be chained with other vulnerabilities.

What is CVE-2022-21882?

CVE-2022-21882 is a local privilege (LPE) escalation vulnerability which allows a local, authenticated attacker to gain elevated local system or administrator privileges through a vulnerability in the Win32k.sys driver.

Is the Vulnerability Exploited in the Wild?

According to the Microsoft advisory, the vulnerability is being exploited in the wild.

Has Microsoft Released an Advisory for CVE-2022-21882?

Yes. See the Appendix for a link to the advisory.

Has Microsoft Released a fix for CVE-2022-21882?

Yes. Microsoft has released a patch as part of regular MS Tuesday on January 11th, 2022.

What is the Status of Coverage?

FortiGuard Labs provide the following IPS coverage for CVE-2022-21882:

MS.Windows.Win32k.CVE-2022-21882.Privilege.Elevation

FortiGuard Labs has released the following AV coverage based on the available POC:

W64/Agent.A93E!exploit.CVE202221882