Windows Mshta Execution In Registry
Description
The following analytic detects the execution of mshta.exe via registry entries to run malicious scripts. It leverages registry activity logs to identify entries containing "mshta," "javascript," "vbscript," or "WScript.Shell." This behavior is significant as it indicates potential fileless malware, such as Kovter, which uses encoded scripts in the registry to persist and execute without files. If confirmed malicious, this activity could allow attackers to maintain persistence, execute arbitrary code, and evade traditional file-based detection methods, posing a significant threat to system integrity and security.
Query · spl
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry
WHERE Registry.registry_value_data = "*mshta*"
OR
Registry.registry_value_data IN ("*javascript:*", "*vbscript:*","*WScript.Shell*")
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)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_mshta_execution_in_registry_filter`
Implementation guide
To successfully implement this search, you must be ingesting data that records registry activity from your hosts to populate the endpoint data model in the registry node. This is typically populated via endpoint detection-and-response product, such as Carbon Black or endpoint data sources, such as Sysmon. The data used for this search is typically generated via logs that report reads and writes to the registry.
Known false positives
- No false positives have been identified at this time.
Analyst notes
Known false positives: No false positives have been identified at this time.