116. That's How Earth Kurma Abuses PowerShell for Data Collection

Hello everyone! As you know, in most cases espionage-related activity clusters need to collect sensitive data before exfiltration. Of course, they can abuse PowerShell to solve this task!

For example, Earth Kurma used the following PowerShell command to collect files of interest:

C:\Windows\system32\cmd.exe /C powershell.exe "dir c:\users -File -Recurse -Include '*.pdf', '*.doc', '*.docx', '*.xls', '*.xlsx', '*.ppt' , '*.pptx'| where LastWriteTime -gt (Get-date).AddDays(-30) | foreach {cmd /c copy $_ /y c:\users\{username}\documents\tmp};echo Finish!"

I think you've spotted many file extensions. We can use this to build our hunting query:

event_type: "processcreatewin"

AND

proc_file_name: "powershell.exe"

AND

cmdline: ("pdf" AND "doc" AND "xls" AND "ppt")

If you want to share more interesting PowerShell abuse examples, you are always welcome!

See you tomorrow!

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