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.
Query · spl
| 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\\*",
"*:\\Program Files \(x86\)\\Windows Kits\\10\\App Certification Kit\\*",
"*:\\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`
Implementation guide
The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
Known false positives
- This detection may require tuning based on third party applications utilizing native Windows binaries in non-standard paths.
Analyst notes
Known false positives: This detection may require tuning based on third party applications utilizing native Windows binaries in non-standard paths.