name: Winword Spawning Cmd
id: 6fcbaedc-a37b-11eb-956b-acde48001122
version: 2
date: '2021-04-22'
author: Michael Haag, Splunk
status: production
type: TTP
description: The following detection identifies Microsoft Word spawning `cmd.exe`.
  Typically, this is not common behavior and not default with winword.exe. Winword.exe
  will generally be found in the following path `C:\Program Files\Microsoft Office\root\Office16`
  (version will vary). Cmd.exe spawning from winword.exe is common for a spearphishing
  attachment and is actively used. Albeit, the command-line will indicate what is
  being executed. During triage, review parallel processes and identify any files
  that may have been written. It is possible that COM is utilized to trampoline the
  child process to `explorer.exe` or `wmiprvse.exe`.
data_source:
- Sysmon Event ID 1
search:
  selection1:
    ParentImage: winword.exe
  selection2:
    OriginalFileName: Cmd.Exe
  selection3:
    Image|endswith: cmd.exe
  condition: selection1 and selection2 and selection3
how_to_implement: To successfully implement this search you need to be ingesting information
  on process that include the name of the process responsible for the changes from
  your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition,
  confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
  endpoint product.
known_false_positives: False positives should be limited, but if any are present,
  filter as needed.
references:
- https://app.any.run/tasks/73af0064-a785-4c0a-ab0d-cde593fe16ef/
tags:
  analytic_story:
  - Spearphishing Attachments
  - DarkCrystal RAT
  asset_type: Endpoint
  confidence: 100
  impact: 70
  message: '$parent_process_name$ on $dest$ by $user$ launched command: $process_name$
    which is very common in spearphishing attacks.'
  mitre_attack_id:
  - T1566
  - T1566.001
  observable:
  - name: dest
    type: Endpoint
    role:
    - Victim
  - name: user
    type: User
    role:
    - Victim
  - name: process_name
    type: Process
    role:
    - Target
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  risk_score: 70
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1566.001/macro/windows-sysmon.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: xmlwineventlog