Techniques
Sample rules
Windows Office Product Spawned Rundll32 With No DLL
- source: splunk
- technicques:
- T1566.001
Description
The following analytic detects any Windows Office Product spawning rundll32.exe without a .dll file extension. This behavior is identified using Endpoint Detection and Response (EDR) telemetry, focusing on process and parent process relationships. This activity is significant as it is a known tactic of the IcedID malware family, which can lead to unauthorized code execution. If confirmed malicious, this could allow attackers to execute arbitrary code, potentially leading to data exfiltration, system compromise, or further malware deployment. Immediate investigation and containment are recommended.
Detection logic
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_office_products_parent` `process_rundll32` (Processes.process!=*.dll*) by Processes.action Processes.dest Processes.original_file_name Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
|`security_content_ctime(lastTime)`
| `windows_office_product_spawned_rundll32_with_no_dll_filter`