splunk-security_content/detections/endpoint/unknown_process_using_the_kerberos_protocol.yml

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