152. Beyond Good Ol' Windows Command Shell

Hello everyone!

It's definitely not a secret that adversaries often abuse various command and scripting interpreters, such as Windows Command Shell and PowerShell.

But in some cases they can bring their own tools to execute commands on the compromised system. For example, NirCmd. It's a small utility that allows threat actors to solve various tasks without displaying any user interface.

Here's an example how Rare Werewolf abused this tool:

schtasks /create /tn "AutoUpdate Driver" /tr "C:\Users\admin\Window\nircmd.exe exec hide C:\Users\admin\Window\bat2.bat" /sc hourly /st 00:00 /ru SYSTEM /f

Definitely, this utility is worth a hunting query:

event_type: "processcreatewin"

AND

proc_file_originalfilename: "nircmd.exe"

AND

cmdline: "hide"

See you tomorrow!

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