LoFP LoFP / other third part application may used this parameter but not so common in base windows environment.

Techniques

Sample rules

Regsvr32 Silent and Install Param Dll Loading

Description

This analytic is to detect a loading of dll using regsvr32 application with silent parameter and dllinstall execution. This technique was seen in several RAT malware similar to remcos, njrat and adversaries to load their malicious DLL on the compromised machine. This TTP may executed by normal 3rd party application so it is better to pivot by the parent process, parent command-line and command-line of the file that execute this regsvr32.

Detection logic


| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_regsvr32` AND Processes.process="*/i*" by Processes.dest Processes.parent_process Processes.process Processes.parent_process_name Processes.process_name Processes.original_file_name Processes.user 
| `drop_dm_object_name(Processes)` 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| where match(process,"(?i)[\-
|\/][Ss]{1}") 
| `regsvr32_silent_and_install_param_dll_loading_filter`