Name:Outbound Network Connection from Java Using Default Ports id:d2c14d28-5c47-11ec-9892-acde48001122 version:13 date:None author:Mauricio Velazco, Lou Stella, Splunk status:production type:TTP Description:The following analytic detects outbound network connections from Java processes to default ports used by LDAP and RMI protocols, which may indicate exploitation of the CVE-2021-44228-Log4j vulnerability.
This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and network traffic logs.
Monitoring this activity is crucial as it can signify an attacker's attempt to perform JNDI lookups and retrieve malicious payloads.
If confirmed malicious, this activity could lead to remote code execution and further compromise of the affected server.
Data_source:
-Sysmon EventID 1 AND Sysmon EventID 3
search:| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Processes WHERE
| tstats `security_content_summariesonly` count FROM datamodel=Network_Traffic.All_Traffic WHERE All_Traffic.dest_port IN ( 389, 636, 1099, 1389 ) BY All_Traffic.action All_Traffic.app All_Traffic.bytes All_Traffic.bytes_in All_Traffic.bytes_out All_Traffic.dest All_Traffic.dest_ip All_Traffic.dest_port All_Traffic.dvc All_Traffic.protocol All_Traffic.protocol_version All_Traffic.src All_Traffic.src_ip All_Traffic.src_port All_Traffic.transport All_Traffic.user All_Traffic.vendor_product All_Traffic.direction All_Traffic.process_id
| `drop_dm_object_name(All_Traffic)`
| rename dest as connection_to_CNC
| rename src as dest ] | table _time dest parent_process_path parent_process_name parent_process process_path process_name process process_hash connection_to_CNC dest_port user | `outbound_network_connection_from_java_using_default_ports_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:Legitimate Java applications may use perform outbound connections to these ports. Filter as needed
References: -https://www.lunasec.io/docs/blog/log4j-zero-day/ -https://www.govcert.admin.ch/blog/zero-day-exploit-targeting-popular-java-library-log4j/ drilldown_searches: name:'View the detection results for - "$dest$"' search:'%original_detection_search% | search dest = "$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'7d' latest_offset:'0' analytic_story:['Log4Shell CVE-2021-44228']
