CVE-2022-24521: 
vulnerability analysis and mitigation

CVE-2022-24521 is a Windows Common Log File System (CLFS) Driver Elevation of Privilege vulnerability discovered in April 2022. The vulnerability was initially discovered as a zero-day being exploited in the wild and was reported to Microsoft by the National Security Agency and researchers Adam Podlosky and Amir Bazine of CrowdStrike (Tenable Blog).

The vulnerability exists in the Windows Common Log File System (CLFS) driver and allows attackers to gain elevated privileges through exploitation of the CClfsLogFcbPhysical::FlushMetadata function. The exploit involves manipulating the CLFSCLIENTCONTEXT structure and using the PreviousMode technique to gain system privileges. The vulnerability received a CVSSv3 score of 7.8 and was rated as 'Exploitation More Likely' according to Microsoft's Exploitability Index (Securelist).

When successfully exploited, the vulnerability allows an attacker to gain elevated system privileges on the affected system. The exploit enables attackers to decrease arbitrary values in memory and use techniques like PreviousMode to gain the ability to read and write kernel memory, effectively achieving complete system control (Securelist).

Microsoft released patches for this vulnerability in April 2022 as part of their Patch Tuesday updates. Organizations are strongly advised to apply the available patches as soon as possible to protect against exploitation (Tenable Blog).