A zero-day vulnerability dubbed ‘DogWalk’, which was first reported over two years ago, has resurfaced. But what does it mean?

Similar to the recently patched ‘Follina’ vulnerability, DogWalk affects the Microsoft Support Diagnostic Tool (MSDT) and was originally dismissed by Microsoft, since the company deemed it as a non-security vulnerability.

DogWalk was initially reported in January 2020 and was recently re-discovered and brought to public attention by a security researcher with the handle ‘j00sean’. While the vulnerability is not known to have been exploited in the wild, a working demonstration has been circulated and the recent interest and widespread exploitation of the similar Follina vulnerability, increases the chances of exploitation.

The vulnerability affects MSDT and is a path traversal flaw that can be exploited to copy an executable file to the Windows Startup folder.

For successful exploitation, the vulnerability is reliant on a degree of social engineering, a specially crafted .diagcab file will need to be distributed via email or, a user will need to be convinced to download the file from the Internet.

.diagcab files are Cabinet files that include a diagnostic configuration file. In this attack, once the startup entry is implanted, the executable file will run the next time Windows is restarted.

What is a zero-day vulnerability?

Allow us to explain in a previous blog.

Reporting

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