Cross-source coverage
T1114.001 / ATT&CK
Email Collection: Local Email Collection
12 rules across 4 sources.
From MITRE ATT&CK 19.2
Adversaries may target user email on local systems to collect sensitive information. Files containing email data can be acquired from a user’s local system, such as Outlook storage or cache files.
Outlook stores data locally in offline data files with an extension of.ost. Outlook 2010 and later supports.ost file sizes up to 50GB, while earlier versions of Outlook support up to 20GB. IMAP accounts in Outlook 2013 (and earlier) and POP accounts use Outlook Data Files (.pst) as opposed to.ost, whereas IMAP accounts in Outlook 2016 (and later) use.ost files. Both types of Outlook data files are typically stored in C:\Users\<username>\Documents\Outlook Files or C:\Users\<username>\AppData\Local\Microsoft\Outlook.
- Tactics
- Collection
- Platforms
- Windows
- Telemetry
-
WinEventLog:SecurityWinEventLog:Sysmon
How MITRE says to detect it DET0047
Detect Local Email Collection via Outlook Data File Access and Command Line Tooling
Windows Analytic 0130
Detection focuses on processes that attempt to locate, access, or exfiltrate local Outlook data files (.pst/.ost) using file system access, native Windows utilities (e.g., PowerShell, WMI), or remote access tools with file browsing capabilities. The behavior chain includes directory enumeration, file access, optional compression or staging, and network transfer.
WinEventLog:SecurityEventCode=4663, 4670, 4656WinEventLog:SysmonEventCode=1WinEventLog:SysmonEventCode=11WinEventLog:SysmonEventCode=3, 22
splunk/security_content
6 rules| Detection | Severity | Format |
|---|---|---|
| Email files written outside of the Outlook directory | Undefined | SPL |
| Mailsniper Invoke functions | Undefined | SPL |
| O365 Email Password and Payroll Compromise Behavior | Undefined | SPL |
| O365 Email Receive and Hard Delete Takeover Behavior | Undefined | SPL |
| O365 Email Send and Hard Delete Exfiltration Behavior | Undefined | SPL |
| O365 Email Send and Hard Delete Suspicious Behavior | Undefined | SPL |
elastic/detection-rules
4 rules| Detection | Severity | Format |
|---|---|---|
| Exchange Mailbox Export via PowerShell | Medium | Elastic TOML |
| Exporting Exchange Mailbox via PowerShell | Medium | Elastic TOML |
| PowerShell Mailbox Collection Script | Medium | Elastic TOML |
| Suspicious Inter-Process Communication via Outlook | Medium | Elastic TOML |
SigmaHQ/sigma
1 rule| Detection | Severity | Format |
|---|---|---|
| Powershell Local Email Collection | Medium | Sigma |
Wazuh Core Ruleset
1 rule| Detection | Severity | Format |
|---|---|---|
| Outlook add-in was loaded by powershell, possible use for email collection | High | Wazuh XML |