Microsoft have released patches as part of August's patch Tuesday release to fix a critical vulnerability that has publicly available exploit code and has been used in attacks. This is being tracked as CVE-2022-34713. More info available from Microsoft here.
DogWalk is due to a vulnerability in Windows Support Diagnostic Tool (MSDT) that attackers can use to gain remote code execution on a victims computer.
The attackers do this by getting a victim to execute a .diagcab file downloaded from the web. This will add it to the Windows startup folder so the next time the victim restarts their computer, it will be executed. This is likely to then download further malware or start other malicious processes.
This vulnerability was originally disclosed in 2020 but it wasn't thought to be a security issue.
This affects all in support versions of Windows, including Windows 11 and Server 2022. Our advice is to test the patch, and roll it out as soon as possible.