Suspicious Inter-Process Communication via Outlook

Last updated 6 months ago on 2025-02-14
Created 3 years ago on 2023-01-11

About

Detects Inter-Process Communication with Outlook via Component Object Model from an unusual process. Adversaries may target user email to collect sensitive information or send email on their behalf via API.
Tags
Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: CollectionData Source: Elastic DefendLanguage: eql
Severity
medium
Risk Score
47
MITRE ATT&CK™

Collection (TA0009)(opens in a new tab or window)

Execution (TA0002)(opens in a new tab or window)

License
Elastic License v2(opens in a new tab or window)

Definition

Rule Type
Event Correlation Rule
Integration Pack
Prebuilt Security Detection Rules
Index Patterns
logs-endpoint.events.process-*
Related Integrations

endpoint(opens in a new tab or window)

Query
sequence with maxspan=1m
[process where host.os.type == "windows" and event.action == "start" and
  (
    process.name : (
      "rundll32.exe", "mshta.exe", "powershell.exe", "pwsh.exe",
      "cmd.exe", "regsvr32.exe", "cscript.exe", "wscript.exe"
    ) or
    (
      (process.code_signature.trusted == false or process.code_signature.exists == false) and
      (process.Ext.relative_file_creation_time <= 500 or process.Ext.relative_file_name_modify_time <= 500)
    )
  )
] by process.entity_id
[process where host.os.type == "windows" and event.action == "start" and process.name : "OUTLOOK.EXE" and
  process.Ext.effective_parent.name != null] by process.Ext.effective_parent.entity_id

Install detection rules in Elastic Security

Detect Suspicious Inter-Process Communication via Outlook in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(opens in a new tab or window).