Name:Remote System Discovery with Net id:9df16706-04a2-41e2-bbfe-9b38b34409d3 version:4 date:2024-11-26 author:Mauricio Velazco, Splunk status:production type:Hunting Description:The following analytic identifies the execution of `net.exe` or `net1.exe` with command-line arguments used to discover remote systems, such as `domain computers /domain`. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant as it indicates potential reconnaissance efforts by adversaries or Red Teams to map out networked systems and Active Directory structures. If confirmed malicious, this behavior could lead to further network exploitation, privilege escalation, or lateral movement within the environment. Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_net` AND (Processes.process="*domain computers*" AND Processes.process=*/do*) OR (Processes.process="*view*" AND Processes.process=*/do*) by Processes.dest Processes.user Processes.parent_process 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)` | `remote_system_discovery_with_net_filter`
how_to_implement: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:Administrators or power users may use this command for troubleshooting. References: -https://attack.mitre.org/techniques/T1018/ -https://thedfirreport.com/2023/05/22/icedid-macro-ends-in-nokoyawa-ransomware/ drilldown_searches:
: tags: analytic_story: - 'Active Directory Discovery' - 'IcedID' asset_type:Endpoint confidence:50 impact:30 message:Remote system discovery enumeration on $dest$ by $user$ mitre_attack_id: - 'T1018' observable: name:'dest' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - 'Processes.dest' - 'Processes.user' - 'Processes.parent_process_name' - 'Processes.parent_process' - 'Processes.original_file_name' - 'Processes.process_name' - 'Processes.process' - 'Processes.process_id' - 'Processes.parent_process_path' - 'Processes.process_path' - 'Processes.parent_process_id' risk_score:15 security_domain:endpoint
