Office Application Startup
- ID
- T1137
- Tactics
- TA0003 Persistence
- Platforms
- Windows, Office Suite
- Data sources
- Process Creation, File Creation, Windows Registry Key Modification, Application Log Content, User Account Modification
- Source
- attack.mitre.org
- MITRE last modified
- 25 Oct 2025
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.[6] These persistence mechanisms can work within Outlook or be used through Office 365.[7]
Sub-techniques (6)
- 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
Detection
- DET0398 Detect Office Startup-Based Persistence via Macros, Forms, and Registry Hooks
Data components: Process Creation, File Creation, Windows Registry Key Modification, Application Log Content, User Account Modification
Mitigations (4)
- 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. [1]
- M1042 Disable or Remove Feature or Program
Follow Office macro security best practices suitable for your environment. Disable Office VBA macros from executing.
Disable Office add-ins. If they are required, follow best practices for securing them by requiring them to be signed and disabling user notification for allowing add-ins. For some add-ins types (WLL, VBA) additional mitigation is likely required as disabling add-ins in the Office Trust Center does not disable WLL nor does it prevent VBA code from executing. [2]
- M1051 Update Software
For the Outlook methods, blocking macros may be ineffective as the Visual Basic engine used for these features is separate from the macro scripting engine.[3] Microsoft has released patches to try to address each issue. Ensure KB3191938 which blocks Outlook Visual Basic and displays a malicious code warning, KB4011091 which disables custom forms by default, and KB4011162 which removes the legacy Home Page feature, are applied to systems.[4]
- M1054 Software Configuration
For the Office Test method, create the Registry key used to execute it and set the permissions to "Read Control" to prevent easy access to the key without administrator permissions or requiring Privilege Escalation. [5]
Groups (2)
References
- win10_asr
- MRWLabs Office Persistence Add-ins
- SensePost Outlook Forms
- SensePost Outlook Home Page
- Palo Alto Office Test Sofacy
- SensePost Ruler GitHub
- TechNet O365 Outlook Rules