Persistence via Microsoft Outlook VBAedit

Detects attempts to establish persistence on an endpoint by installing a rogue Microsoft Outlook VBA Template.

Rule type: eql

Rule indices:

  • logs-endpoint.events.*
  • winlogbeat-*
  • logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Persistence

Version: 3 (version history)

Added (Elastic Stack release): 7.11.0

Last modified (Elastic Stack release): 7.12.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positivesedit

A legitimate VBA for Outlook is usually configured interactively via OUTLOOK.EXE.

Rule queryedit

file where event.type != "deletion" and file.path :
"C:\\Users\\*\\AppData\\Roaming\\Microsoft\\Outlook\\VbaProject.OTM"

Threat mappingedit

Framework: MITRE ATT&CKTM

Rule version historyedit

Version 3 (7.12.0 release)
  • Updated query, changed from:

    file where event.type != "deletion" and wildcard(file.path,
    "C:\\Users\\*\\AppData\\Roaming\\Microsoft\\Outlook\\VbaProject.OTM")
Version 2 (7.11.2 release)
  • Formatting only