name: Unknown Process Using The Kerberos Protocol id: c91a0852-9fbb-11ec-af44-acde48001122 version: 1 date: '2022-03-09' author: Mauricio Velazco, Splunk type: TTP datamodel: - Endpoint - Network_Traffic description: The following analytic identifies a process performing an outbound connection on port 88 used by default by the network authentication protocol Kerberos. Typically, on a regular Windows endpoint, only the lsass.exe process is the one tasked with connecting to the Kerberos Distribution Center to obtain Kerberos tickets. Identifying an unknown process using this protocol may be evidence of an adversary abusing the Kerberos protocol. search: '| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Processes where Processes.process_name!=lsass.exe by _time Processes.process_id Processes.process_name Processes.dest Processes.process_path Processes.process Processes.parent_process_name | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | join process_id [| tstats `security_content_summariesonly` count FROM datamodel=Network_Traffic.All_Traffic where All_Traffic.dest_port = 88 by All_Traffic.process_id All_Traffic.dest All_Traffic.dest_port | `drop_dm_object_name(All_Traffic)` ] | table _time dest parent_process_name process_name process_path process process_id dest_port | `unknown_process_using_the_kerberos_protocol_filter`' how_to_implement: To successfully implement this search, you must be ingesting your endpoint events and populating the Endpoint and Network data models. known_false_positives: Custom applications may leverage the Kerberos protocol. Filter as needed. references: - https://stealthbits.com/blog/how-to-detect-overpass-the-hash-attacks/ - https://www.thehacker.recipes/ad/movement/kerberos/ptk tags: analytic_story: - Active Directory Kerberos Attacks dataset: - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1550/rubeus/windows-security.log kill_chain_phases: - Reconnaissance mitre_attack_id: - T1550 product: - Splunk Enterprise - Splunk Enterprise Security - Splunk Cloud required_fields: - _time - All_Traffic.dest_ip - All_Traffic.dest_port - All_Traffic.src_ip - Processes.process_id - Processes.process_name - Processes.dest - Processes.process_path - Processes.process - Processes.parent_process_name security_domain: endpoint impact: 60 confidence: 60 risk_score: 36 context: - Source:Endpoint - Stage:Privilege Escalation - Stage:Lateral Movement message: '' observable: - name: src_ip type: IP Address role: - Attacker - name: dest_ip type: IP Address role: - Victim asset_type: Endpoint