Disable Defender Spynet Reporting
Description
The following analytic detects the modification of the registry to disable Windows Defender SpyNet reporting. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the registry path associated with Windows Defender SpyNet settings. This activity is significant because disabling SpyNet reporting can prevent Windows Defender from sending telemetry data, potentially allowing malicious activities to go undetected. If confirmed malicious, this action could enable an attacker to evade detection, maintain persistence, and carry out further attacks without being flagged by Windows Defender.
Query · spl
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry WHERE (Registry.registry_path = "*\\Microsoft\\Windows Defender\\SpyNet*" Registry.registry_value_name = SpynetReporting 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 | `drop_dm_object_name(Registry)` | where isnotnull(registry_value_data) | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `disable_defender_spynet_reporting_filter`
Implementation guide
To successfully implement this search, you need to be ingesting logs with the registry value name, registry path, and registry value data from your endpoints. If you are using Sysmon, you must have at least version 2.0 of the official Sysmon TA. https://splunkbase.splunk.com/app/5709
Known false positives
- admin or user may choose to disable windows defender product
Analyst notes
Known false positives: admin or user may choose to disable windows defender product