Persistence via Microsoft Office AddIns

Elastic Stack Serverless Security

Detects attempts to establish persistence on an endpoint by abusing Microsoft Office add-ins.

Rule type: eql

Rule indices:

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

Severity: high

Risk score: 73

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://labs.mwrinfosecurity.com/blog/add-in-opportunities-for-office-persistence/

Tags:

• Elastic
• Host
• Windows
• Threat Detection
• Persistence

Version: 6

Rule authors:

• Elastic

Rule license: Elastic License v2

file where event.type != "deletion" and
 file.extension : ("wll","xll","ppa","ppam","xla","xlam") and
 file.path :
    (
    "C:\\Users\\*\\AppData\\Roaming\\Microsoft\\Word\\Startup\\*",
    "C:\\Users\\*\\AppData\\Roaming\\Microsoft\\AddIns\\*",
    "C:\\Users\\*\\AppData\\Roaming\\Microsoft\\Excel\\XLSTART\\*"
    )

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Persistence
  • ID: TA0003
  • Reference URL: https://attack.mitre.org/tactics/TA0003/

• Technique:

  • Name: Office Application Startup
  • ID: T1137
  • Reference URL: https://attack.mitre.org/techniques/T1137/