Cross-source coverage
T1137.004 / ATT&CK
Office Application Startup: Outlook Home Page
From MITRE ATT&CK 19.2
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.
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.
- Tactics
- Persistence
- Platforms
- Windows · Office Suite
- Telemetry
-
WinEventLog:SysmonWinEventLog:ApplicationWinEventLog:PowerShellm365:unifiedm365:messagetrace
How MITRE says to detect it DET0177
Detect Persistence via Outlook Home Page Exploitation
Windows Analytic 0502
Adversary uses a tool like Ruler to configure a malicious Outlook folder Home Page that loads a remote or embedded HTML payload upon folder interaction. Execution chain begins with Outlook launching, a specific folder being accessed, and a suspicious child process being spawned or COM-based execution invoked.
WinEventLog:SysmonEventCode=1WinEventLog:SysmonEventCode=7WinEventLog:ApplicationOutlook logs indicating failure to load or render HTML page in Home Page viewWinEventLog:PowerShellExecution of PowerShell script to enumerate or remove malicious Home Page folder config
Office Suite Analytic 0503
Malicious HTML or script is rendered as a Home Page for a specific Outlook folder. Outlook accesses that folder, loads remote content, and executes embedded JavaScript or ActiveX/COM logic resulting in unauthorized actions or local execution.
m365:unifiedFolder configuration updated with external or HTML-formatted Home Page via Set-MailboxFolderm365:messagetraceInbound email triggering Outlook to auto-access folder tied to malicious Home Page
elastic/detection-rules
1 rule| Detection | Severity | Format |
|---|---|---|
| Outlook Home Page Registry Modification | High | Elastic TOML |
elastic/protections-artifacts
1 rule| Detection | Severity | Format |
|---|---|---|
| Outlook Home Page Registry Modification | Undefined | Elastic TOML |