Detection rules › Splunk

Windows Impair Defense Change Win Defender Quick Scan Interval

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects modifications to the Windows registry that change the Windows Defender Quick Scan Interval. It leverages data from the Endpoint.Registry data model, focusing on changes to the "QuickScanInterval" registry path. This activity is significant because altering the scan interval can impair Windows Defender's ability to detect malware promptly, potentially allowing threats to persist undetected. If confirmed malicious, this modification could enable attackers to bypass security measures, maintain persistence, and execute further malicious activities without being detected by quick scans.

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="*\\Windows Defender\\Scan\\QuickScanInterval" 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.registry_patheq
  • "*\\Windows Defender\\Scan\\QuickScanInterval"