Detection rules › Splunk

Windows Impair Defense Delete Win Defender Profile Registry

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects the deletion of the Windows Defender main profile registry key. It leverages data from the Endpoint.Registry datamodel, specifically monitoring for deleted actions within the Windows Defender registry path. This activity is significant as it indicates potential tampering with security defenses, often associated with Remote Access Trojans (RATs) and other malware. If confirmed malicious, this action could allow an attacker to disable Windows Defender, reducing the system's ability to detect and respond to further malicious activities, thereby compromising endpoint security.

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1562.001 Impair Defenses: Disable or Modify Tools

Event coverage

ProviderEvent IDTitle
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: tstats

tstats WHERE Registry.action="deleted" Registry.registry_path="*\\Policies\\Microsoft\\Windows Defender" 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

Stage 2: search

search

Stage 3: search

search

Stage 4: search

search

Stage 5: search

search `macro`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Registry.actioneq
  • deleted corpus 8 (splunk 8)
Registry.registry_patheq
  • "*\\Policies\\Microsoft\\Windows Defender"