LoFP LoFP / this detection may require tuning based on third party applications utilizing native windows binaries in non-standard paths.

Techniques

Sample rules

System Processes Run From Unexpected Locations

Description

The following analytic identifies system processes running from unexpected locations outside of paths such as C:\Windows\System32\ or C:\Windows\SysWOW64. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process paths, names, and hashes. This activity is significant as it may indicate a malicious process attempting to masquerade as a legitimate system process. If confirmed malicious, this behavior could allow an attacker to execute code, escalate privileges, or maintain persistence within the environment, posing a significant security risk.

Detection logic


| tstats `security_content_summariesonly` 
  count min(_time) as firstTime max(_time) as lastTime 
  FROM datamodel=Endpoint.Processes where 
  NOT Processes.process_path IN (
    "*:\\$WINDOWS.~BT\\*",
    "*:\\$WinREAgent\\*",
    "*:\\Windows\\SoftwareDistribution\\*",
    "*:\\Windows\\System32\\*",
    "*:\\Windows\\SystemTemp\\*",
    "*:\\Windows\\SysWOW64\\*",
    "*:\\Windows\\uus\\*",
    "*:\\Windows\\WinSxS\\*",
  )
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)`

| lookup update=true is_windows_system_file filename as process_name OUTPUT systemFile

| search systemFile=true

| `system_processes_run_from_unexpected_locations_filter`