LoFP LoFP / false positives may be present from automation based applications (sccm), filtering may be required. in addition, break the query out based on volume of usage. filter process names or f

Techniques

Sample rules

Windows MOF Event Triggered Execution via WMI

Description

The following anaytic identifies MOFComp.exe loading a MOF file. The Managed Object Format (MOF) compiler parses a file containing MOF statements and adds the classes and class instances defined in the file to the WMI repository. Typically, MOFComp.exe does not reach out to the public internet or load a MOF file from User Profile paths. A filter and consumer is typically registered in WMI. Review parallel processes and query WMI subscriptions to gather artifacts. The default path of mofcomp.exe is C:\Windows\System32\wbem.

Detection logic


| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.parent_process_name IN ("cmd.exe", "powershell.exe") Processes.process_name=mofcomp.exe) OR (Processes.process_name=mofcomp.exe Processes.process IN ("*\\AppData\\Local\\*","*\\Users\\Public\\*", "*\\WINDOWS\\Temp\\*")) by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id 
| `drop_dm_object_name(Processes)` 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `windows_mof_event_triggered_execution_via_wmi_filter`