Name:Network Connection Discovery With Netstat id:2cf5cc25-f39a-436d-a790-4857e5995ede version:5 date:2025-03-14 author:Mauricio Velazco, Splunk status:production type:Hunting Description:The following analytic detects the execution of `netstat.exe` with command-line arguments to list network connections on a system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, command-line executions, and parent processes. This activity is significant as both Red Teams and adversaries use `netstat.exe` for situational awareness and Active Directory discovery. If confirmed malicious, this behavior could allow attackers to map network connections, identify critical systems, and plan further lateral movement or data exfiltration. 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 (Processes.process_name="netstat.exe") (Processes.process=*-a*) 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)` | `network_connection_discovery_with_netstat_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/T1049/ -https://www.microsoft.com/en-us/security/blog/2023/05/24/volt-typhoon-targets-us-critical-infrastructure-with-living-off-the-land-techniques/ drilldown_searches:
: tags: analytic_story: - 'CISA AA22-277A' - 'Windows Post-Exploitation' - 'Active Directory Discovery' - 'CISA AA23-347A' - 'Prestige Ransomware' - 'Qakbot' - 'PlugX' - 'Medusa Ransomware' - 'Volt Typhoon' asset_type:Endpoint mitre_attack_id: - 'T1049' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
