Adversaries may leverage Microsoft Office-based applications for persistence between startups. Microsoft Office is a fairly common application suite on Windows-based operating systems within an enterprise network. There are multiple mechanisms that can be used with Office for persistence when an Office-based application is started; this can include the use of Office Template Macros and add-ins.A variety of features have been discovered in Outlook that can be abused to obtain persistence, such as Outlook rules, forms, and Home Page.(Citation: SensePost Ruler GitHub) These persistence mechanisms can work within Outlook or be used through Office 365.(Citation: TechNet O365 Outlook Rules)
As outlined in MDSEC's Blog post https://www.mdsec.co.uk/2020/11/a-fresh-outlook-on-mail-based-persistence/ it is possible to use Outlook Macro as a way to achieve persistance and execute arbitrary commands. This transform Outlook into a C2. Too achieve this two things must happened on the syste
- The macro security registry value must be set to '4'
- A file called VbaProject.OTM must be created in the Outlook Folder.
Supported Platforms: Windows
reg add "HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Security" /t REG_DWORD /d 4
if not exist %APPDATA%\Microsoft\Outlook ( md %APPDATA%\Microsoft\Outlook\ )
echo "Atomic Red Team TEST" > %APPDATA%\Microsoft\Outlook\VbaProject.OTM
reg delete "HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Security" /f
del %APPDATA%\Microsoft\Outlook\VbaProject.OTM