Detection rules › Splunk

Windows Impair Defense Disable Win Defender Signature Retirement

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects modifications to the Windows registry that disable Windows Defender Signature Retirement. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the DisableSignatureRetirement registry setting. This activity is significant because disabling signature retirement can prevent Windows Defender from removing outdated antivirus signatures, potentially reducing its effectiveness in detecting threats. If confirmed malicious, this action could allow an attacker to evade detection by using older, less relevant signatures, thereby compromising the system's security posture.

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\\NIS\\Consumers\\IPS\\DisableSignatureRetirement" Registry.registry_value_data="0x00000001" 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\\NIS\\Consumers\\IPS\\DisableSignatureRetirement"
Registry.registry_value_dataeq
  • "0x00000001" corpus 42 (splunk 42)