Detect Prohibited Applications Spawning cmd exe
Description
The following analytic detects executions of cmd.exe spawned by processes that are commonly abused by attackers and do not typically launch cmd.exe. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process GUID, process name, parent process, and command-line executions. This activity is significant because it may indicate an attempt to execute unauthorized commands or scripts, often a precursor to further malicious actions. If confirmed malicious, this behavior could lead to unauthorized code execution, privilege escalation, or persistence within the environment.
Query · spl
| tstats `security_content_summariesonly` count values(Processes.process)
as process min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name=cmd.exe OR Processes.original_file_name=Cmd.Exe)
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)`
|search [
| inputlookup prohibited_apps_launching_cmd
| rename prohibited_applications as parent_process_name
| eval parent_process_name="*" . parent_process_name
| table parent_process_name
]
| `detect_prohibited_applications_spawning_cmd_exe_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
- There are circumstances where an application may legitimately execute and interact with the Windows command-line interface. Investigate and modify the lookup file, as appropriate.
Analyst notes
Known false positives: There are circumstances where an application may legitimately execute and interact with the Windows command-line interface. Investigate and modify the lookup file, as appropriate.