Office Application Startup: Outlook Home Page
- ID
- T1137.004
- Tactics
- TA0003 Persistence
- Sub-technique of
- T1137 Office Application Startup
- Platforms
- Windows, Office Suite
- Data sources
- Process Creation, Module Load, Application Log Content, Command Execution
- Source
- attack.mitre.org
- MITRE last modified
- 25 Oct 2025
Adversaries may abuse Microsoft Outlook's Home Page feature to obtain persistence on a compromised system. Outlook Home Page is a legacy feature used to customize the presentation of Outlook folders. This feature allows for an internal or external URL to be loaded and presented whenever a folder is opened. A malicious HTML page can be crafted that will execute code when loaded by Outlook Home Page.[3]
Once malicious home pages have been added to the user’s mailbox, they will be loaded when Outlook is started. Malicious Home Pages will execute when the right Outlook folder is loaded/reloaded.[3]
Detection
- DET0177 Detect Persistence via Outlook Home Page Exploitation
Data components: Process Creation, Module Load, Application Log Content, Command Execution
Mitigations (2)
- 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]
- 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.[2] 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.[3]
Groups (1)
Software (1)
References
- win10_asr
- SensePost Outlook Forms
- SensePost Outlook Home Page