name: Disable Logs Using WevtUtil
id: 236e7c8e-c9d9-11eb-a824-acde48001122
version: 1
date: '2021-06-10'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: This search is to detect execution of wevtutil.exe to disable logs. This
  technique was seen in several ransomware to disable the event logs to evade alerts
  and detections.
data_source:
- Sysmon Event ID 1
search:
  selection1:
    CommandLine: '*sl*'
    Image|endswith: wevtutil.exe
  selection2:
    CommandLine: '*/e:false*'
  condition: selection1 and selection2
how_to_implement: To successfully implement this search, you need to be ingesting
  logs with the process name, parent process, and command-line executions from your
  endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the
  Sysmon TA.
known_false_positives: network operator may disable audit event logs for debugging
  purposes.
references:
- https://www.bleepingcomputer.com/news/security/new-ransom-x-ransomware-used-in-texas-txdot-cyberattack/
tags:
  analytic_story:
  - Ransomware
  asset_type: Endpoint
  confidence: 80
  impact: 30
  message: WevtUtil.exe used to disable Event Logging on $dest
  mitre_attack_id:
  - T1070
  - T1070.001
  observable:
  - name: dest
    type: Endpoint
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  risk_score: 24
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/ransomware_ttp/data1/windows-sysmon.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: xmlwineventlog