Windows Modify Registry WuServer

Original Source: [splunk source]
Name:Windows Modify Registry WuServer
id:a02ad386-e26d-44ce-aa97-6a46cee31439
version:6
date:2024-11-13
author:Teoderick Contreras, Splunk
status:production
type:Hunting
Description:The following analytic detects suspicious modifications to the Windows Update Server (WUServer) registry settings. It leverages data from the Endpoint.Registry data model to identify changes in the registry path associated with Windows Update configurations. This activity is significant because adversaries, including malware like RedLine Stealer, exploit this technique to bypass detection and deploy additional payloads. If confirmed malicious, this registry modification could allow attackers to evade defenses, potentially leading to further system compromise and persistent unauthorized access.
Data_source:
  • -Sysmon EventID 13
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where Registry.registry_path="*\\SOFTWARE\\Policies\\Microsoft\\Windows\\WindowsUpdate\\WUServer" by Registry.action Registry.dest Registry.process_guid Registry.process_id Registry.registry_hive Registry.registry_path Registry.registry_key_name Registry.registry_value_data Registry.registry_value_name Registry.registry_value_type Registry.status Registry.user Registry.vendor_product
| `drop_dm_object_name(Registry)`
| `security_content_ctime(lastTime)`
| `security_content_ctime(firstTime)`
| `windows_modify_registry_wuserver_filter`


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:Administrators may enable or disable this feature that may cause some false positive.
References:
  -https://learn.microsoft.com/de-de/security-updates/windowsupdateservices/18127499
drilldown_searches:
  :
tags:
  analytic_story:
    - 'RedLine Stealer'
  asset_type:Endpoint
  mitre_attack_id:
    - 'T1112'
  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/malware/redline/modify_registry/sysmon.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None

Related Analytic Stories


RedLine Stealer