UtilityFunctions.ps1

type: OSScripts

PowerShell Diagnostic Script

Full path

C:\Windows\diagnostics\system\Networking\UtilityFunctions.ps1

Commands

ExecuteUser T1216

Execute proxied payload with Microsoft signed binary

powershell.exe -ep bypass -command "set-location -path c:\windows\diagnostics\system\networking; import-module .\UtilityFunctions.ps1; RegSnapin ..\..\..\..\temp\unsigned.dll;[Program.Class]::Main()"

Proxy execute Managed DLL with PowerShell

os: Windows 10 21H1 (likely other versions as well), Windows 11

Execute: DLL (.NET)

Detection

Sigma https://github.com/SigmaHQ/sigma/blob/0.21-688-gd172b136b/rules/windows/process_creation/proc_creation_win_lolbas_utilityfunctions.yml

Resources

https://twitter.com/nickvangilder/status/1441003666274668546

acknowledgement: Nick VanGilder @nickvangilder