windows_eventlog_cleared_via_wevtutil.yml

name: Windows Eventlog Cleared Via Wevtutil
id: fdb829a8-db84-4832-b64b-3e964cd44f01
version: 1
date: '2025-04-15'
author: Nasreddine Bencherchali, Splunk
status: production
type: Anomaly
description: |
  The following analytic detects the usage of wevtutil.exe with the "clear-log" parameter in order to clear the contents of logs. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant because clearing event logs can be an attempt to cover tracks after malicious actions, hindering forensic investigations. If confirmed malicious, this behavior could allow an attacker to erase evidence of their activities, making it difficult to trace their actions and understand the full scope of the compromise.
data_source:
- Sysmon EventID 1
- Windows Event Log Security 4688
- CrowdStrike ProcessRollup2
search: '| tstats `security_content_summariesonly` values(Processes.process) as process
  min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes
  where Processes.process_name=wevtutil.exe Processes.process IN ("* cl *", "*clear-log*")
  by Processes.action Processes.dest Processes.original_file_name
  Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
  Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
  Processes.process Processes.process_exec Processes.process_guid Processes.process_hash
  Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path
  Processes.user Processes.user_id Processes.vendor_product | `drop_dm_object_name(Processes)`
  | `security_content_ctime(firstTime)` |`security_content_ctime(lastTime)` | `windows_eventlog_cleared_via_wevtutil_filter`'
how_to_implement: The detection is based on data that originates from Endpoint Detection
  and Response (EDR) agents. These agents are designed to provide security-related
  telemetry from the endpoints where the agent is installed. To implement this search,
  you must ingest logs that contain the process GUID, process name, and parent process.
  Additionally, you must ingest complete command-line executions. These logs must
  be processed using the appropriate Splunk Technology Add-ons that are specific to
  the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint`
  data model. Use the Splunk Common Information Model (CIM) to normalize the field
  names and speed up the data modeling process.
known_false_positives: The wevtutil.exe application is a legitimate Windows event log utility. Administrators may use it to manage Windows event logs.
references:
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1070.001/T1070.001.md
drilldown_searches:
- name: View the detection results for - "$dest$" and "$user$"
  search: '%original_detection_search% | search  dest = "$dest$" user = "$user$"'
  earliest_offset: $info_min_time$
  latest_offset: $info_max_time$
- name: View risk events for the last 7 days for - "$dest$" and "$user$"
  search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$",
    "$user$") starthoursago=168  | stats count min(_time) as firstTime max(_time)
    as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk
    Message" values(analyticstories) as "Analytic Stories" values(annotations._all)
    as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics"
    by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
  earliest_offset: $info_min_time$
  latest_offset: $info_max_time$
rba:
  message: Eventlog was cleared using the Wevtutil.exe utility on $dest$ by $user$
  risk_objects:
  - field: dest
    type: system
    score: 28
  - field: user
    type: user
    score: 28
  threat_objects: []
tags:
  analytic_story:
  - Windows Log Manipulation
  - Ransomware
  - Rhysida Ransomware
  - Clop Ransomware
  - CISA AA23-347A
  - ShrinkLocker
  asset_type: Endpoint
  mitre_attack_id:
  - T1070.001
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1070.001/windows_pwh_log_cleared/wevtutil_clear_log.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: XmlWinEventLog