| ID | Name |
|---|---|
| T1137.001 | Office Template Macros |
| T1137.002 | Office Test |
| T1137.003 | Outlook Forms |
| T1137.004 | Outlook Home Page |
| T1137.005 | Outlook Rules |
| T1137.006 | Add-ins |
Adversaries may abuse Microsoft Office add-ins to obtain persistence on a compromised system. Office add-ins can be used to add functionality to Office programs. [1] There are different types of add-ins that can be used by the various Office products; including Word/Excel add-in Libraries (WLL/XLL), VBA add-ins, Office Component Object Model (COM) add-ins, automation add-ins, VBA Editor (VBE), Visual Studio Tools for Office (VSTO) add-ins, and Outlook add-ins. [2][3]
Add-ins can be used to obtain persistence because they can be set to execute code when an Office application starts.
| ID | Name | Description |
|---|---|---|
| S0268 | Bisonal |
Bisonal has been loaded through a |
| G0019 | Naikon |
Naikon has used the RoyalRoad exploit builder to drop a second stage loader, intel.wll, into the Word Startup folder on the compromised host.[5] |
| ID | Mitigation | Description |
|---|---|---|
| M1040 | Behavior Prevention on Endpoint |
On Windows 10, enable Attack Surface Reduction (ASR) rules to prevent Office applications from creating child processes and from writing potentially malicious executable content to disk. [6] |
Monitor and validate the Office trusted locations on the file system and audit the Registry entries relevant for enabling add-ins.[7][2]
Collect process execution information including process IDs (PID) and parent process IDs (PPID) and look for abnormal chains of activity resulting from Office processes. Non-standard process execution trees may also indicate suspicious or malicious behavior