LoFP LoFP / minimal. but network operator can use this application to load dll.

Techniques

Sample rules

Regsvr32 with Known Silent Switch Cmdline

Description

The following analytic detects the execution of Regsvr32.exe with the silent switch to load DLLs. This behavior is identified using Endpoint Detection and Response (EDR) telemetry, focusing on command-line executions containing the -s or /s switches. This activity is significant as it is commonly used in malware campaigns, such as IcedID, to stealthily load malicious DLLs. If confirmed malicious, this could allow an attacker to execute arbitrary code, download additional payloads, and potentially compromise the system further. Immediate investigation and endpoint isolation are recommended.

Detection logic


| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
  WHERE `process_regsvr32`
  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)`

| where match(process,"(?i)[\-

| \/][Ss]{1}")

| `regsvr32_with_known_silent_switch_cmdline_filter`