Detection rules › Splunk

Windows Modify Registry Auto Minor Updates

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic identifies a suspicious modification to the Windows auto update configuration registry. It detects changes to the registry path "*\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU\AutoInstallMinorUpdates" with a value of "0x00000000". This activity is significant as it is commonly used by adversaries, including malware like RedLine Stealer, to bypass detection and deploy additional payloads. If confirmed malicious, this modification could allow attackers to evade defenses, potentially leading to further system compromise and exploitation of zero-day vulnerabilities.

MITRE ATT&CK coverage

TacticTechniques
PersistenceT1112 Modify Registry
Defense EvasionT1112 Modify Registry

Event coverage

ProviderEvent IDTitle
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: tstats

tstats WHERE Registry.registry_path="*\\SOFTWARE\\Policies\\Microsoft\\Windows\\WindowsUpdate\\AU\\AutoInstallMinorUpdates" Registry.registry_value_data="0x00000000" 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
  • "*\\SOFTWARE\\Policies\\Microsoft\\Windows\\WindowsUpdate\\AU\\AutoInstallMinorUpdates"
Registry.registry_value_dataeq
  • "0x00000000" corpus 27 (splunk 27)