Detection rules › Splunk

Disable Defender AntiVirus Registry

Author
Teoderick Contreras, Splunk, Steven Dick
Source
upstream

The following analytic detects the modification of Windows Defender registry settings to disable antivirus and antispyware protections. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to registry paths associated with Windows Defender policies. This activity is significant because disabling antivirus protections is a common tactic used by adversaries to evade detection and maintain persistence on compromised systems. If confirmed malicious, this action could allow attackers to execute further malicious activities undetected, leading to potential data breaches, system compromise, and further propagation of malware within the network.

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.registry_path="*\\Policies\\Microsoft\\Windows Defender*" Registry.registry_value_data=0x00000001 Registry.registry_value_name IN ("DisableAntiSpyware", "DisableAntiVirus") 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: where

where isnotnull(registry_value_data)

Stage 4: search

search

Stage 5: search

search

Stage 6: 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.registry_patheq
  • "*\\Policies\\Microsoft\\Windows Defender*"
Registry.registry_value_dataeq
  • 0x00000001 corpus 12 (splunk 12)
Registry.registry_value_namein
  • "DisableAntiSpyware"
  • "DisableAntiVirus"