Detection rules › Splunk

Windows Defender Exclusion Registry Entry

Author
Teoderick Contreras, Splunk, Steven Dick
Source
upstream

The following analytic detects modifications to the Windows Defender exclusion registry entries. It leverages endpoint registry data to identify changes in the registry path "\SOFTWARE\Policies\Microsoft\Windows Defender\Exclusions\". This activity is significant because adversaries often modify these entries to bypass Windows Defender, allowing malicious code to execute without detection. If confirmed malicious, this behavior could enable attackers to evade antivirus defenses, maintain persistence, and execute further malicious activities undetected.

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="*\\SOFTWARE\\Policies\\Microsoft\\Windows Defender\\Exclusions\\*" 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
  • "*\\SOFTWARE\\Policies\\Microsoft\\Windows Defender\\Exclusions\\*"