Registry Keys Used For Privilege Escalation
Description
The following analytic detects modifications to registry keys under "Image File Execution Options" that can be used for privilege escalation. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to registry paths and values like GlobalFlag and Debugger. This activity is significant because attackers can use these modifications to intercept executable calls and attach malicious binaries to legitimate system binaries. If confirmed malicious, this could allow attackers to execute arbitrary code with elevated privileges, leading to potential system compromise and persistent access.
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 NT\\CurrentVersion\\Image File Execution Options*") AND (Registry.registry_value_name=GlobalFlag OR Registry.registry_value_name=Debugger)) 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)` | `registry_keys_used_for_privilege_escalation_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
- There are many legitimate applications that must execute upon system startup and will use these registry keys to accomplish that task.
Analyst notes
Known false positives: There are many legitimate applications that must execute upon system startup and will use these registry keys to accomplish that task.