256. That's How Adversaries Abuse PowerShell Cmdlets

Hello everyone!

I've brought you another PowerShell (T1059.001) procedure you may use in your threat hunting missions! 

Let's look inside a new report on Head Mare (we track this cluster as Rainbow Hyena). The adversary downloaded archives with additional backdoors from a remote server and used PowerShell to expand it:

powershell expand-archive -force -path C:\ProgramData\YandexUpdate\update.zip -destinationpath C:\ProgramData\YandexUpdate\

The threat actors chose ProgramData as a staging folder, so we can use it to build the query and look for susoicious events:

event_type: "processcreatewin"

AND

proc_file_path: "powershell.exe"

AND

cmdline: ("expand-archive" AND "programdata")

See you tomorrow!

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