Windows Suspect Process With Authentication Traffic

name: Windows Suspect Process With Authentication Traffic
id: 953322db-128a-4ce9-8e89-56e039e33d98
version: 11
creation_date: '2023-07-28'
modification_date: '2026-05-13'
author: Steven Dick
status: production
type: Anomaly
description: The following analytic detects executables running from public or temporary locations that are communicating over Windows domain authentication ports/protocols such as LDAP (389), LDAPS (636), and Kerberos (88). It leverages network traffic data to identify processes originating from user-controlled directories. This activity is significant because legitimate applications rarely run from these locations and attempt domain authentication, making it a potential indicator of compromise. If confirmed malicious, attackers could leverage this to access domain resources, potentially leading to further exploitation and lateral movement within the network.
data_source:
    - Sysmon EventID 3
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(All_Traffic.process_id) as process_id  from datamodel=Network_Traffic.All_Traffic where All_Traffic.dest_port IN ("88","389","636")  AND All_Traffic.app IN ("*\\users\\*", "*\\programdata\\*", "*\\temp\\*", "*\\Windows\\Tasks\\*", "*\\appdata\\*", "*\\perflogs\\*") by All_Traffic.action All_Traffic.app All_Traffic.dest All_Traffic.dest_ip All_Traffic.dest_port All_Traffic.direction 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 | `drop_dm_object_name(All_Traffic)`  | rex field=app ".*\\\(?<process_name>.*)$" | `security_content_ctime(firstTime)`  | `security_content_ctime(lastTime)` | `windows_suspect_process_with_authentication_traffic_filter`'
how_to_implement: To implement this analytic, Sysmon should be installed in the environment and generating network events for  userland and/or known public writable locations.
known_false_positives: Known applications running from these locations for legitimate purposes. Targeting only kerberos (port 88) may significantly reduce noise.
references:
    - https://attack.mitre.org/techniques/T1069/002/
    - https://book.hacktricks.xyz/network-services-pentesting/pentesting-kerberos-88
intermediate_findings:
    entities:
        - field: src
          type: system
          score: 20
          message: The process $process_name$ on $src$ has been communicating with $dest$ on $dest_port$.
        - field: dest
          type: system
          score: 20
          message: The process $process_name$ on $src$ has been communicating with $dest$ on $dest_port$.
        - field: user
          type: user
          score: 20
          message: The process $process_name$ on $src$ has been communicating with $dest$ on $dest_port$.
threat_objects:
    - field: process_name
      type: process_name
analytic_story:
    - Active Directory Discovery
asset_type: Endpoint
mitre_attack_id:
    - T1087.002
    - T1204.002
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint