Techniques
Sample rules
Disabling Windows Local Security Authority Defences via Registry
- source: splunk
- technicques:
- T1556
Description
The following analytic identifies the deletion of registry keys that disable Local Security Authority (LSA) protection and Microsoft Defender Device Guard. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on registry actions and paths associated with LSA and Device Guard settings. This activity is significant because disabling these defenses can leave a system vulnerable to various attacks, including credential theft and unauthorized code execution. If confirmed malicious, this action could allow attackers to bypass critical security mechanisms, leading to potential system compromise and persistent access.
Detection logic
| tstats `security_content_summariesonly` min(_time) as _time from datamodel=Endpoint.Registry where Registry.registry_path IN ("*\\SYSTEM\\CurrentControlSet\\Control\\Lsa\\LsaCfgFlags", "*\\SOFTWARE\\Policies\\Microsoft\\Windows\\DeviceGuard\\*", "*\\SYSTEM\\CurrentControlSet\\Control\\Lsa\\RunAsPPL") Registry.action IN (deleted, unknown) by Registry.action Registry.registry_path Registry.process_guid Registry.dest Registry.user
| `drop_dm_object_name(Registry)`
| join type=outer process_guid [
| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Processes by Processes.user Processes.process_name Processes.process Processes.dest Processes.parent_process_name Processes.parent_process Processes.process_guid
| `drop_dm_object_name(Processes)`]
| table _time action dest user parent_process_name parent_process process_name process process_guid registry_path
| `disabling_windows_local_security_authority_defences_via_registry_filter`