314. Adversaries Abuse PowerShell to Create Shortcuts for Persistence

Hello everyone!

Let's keep digging in PowerShell procedures, and this time we'll look at how adversaries leverage it for persistence.

And today's example is generously provided by Lazarus (or Lazer Werewolf among many other names). The adversary used PowerShell to create a shortcut in the startup folder and enable persistence:

cmd.exe /C powershell -Command "$s = (New-Object -COMWScript.Shell).CreateShortcut('C:\\ProgramData\\USOShared\\Micro.lnk'); $s.TargetPath = 'C:\\Windows\\System32\\rundll32.exe'; $s.Arguments = '\"[USOPrivate.dll path]\" LoadMimi \"C:\\Windows\\System32\\cmd.exe\"'; $s.Save()"

Similar behavior markers may be related to legitimate activity, so it's a good target for hunting:

event_type: "processcreatewin"

AND

proc_file_path: "powershell.exe"

AND

cmdline: "CreateShortcut"

See you tomorrow!

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