splunk-security_content/detections/endpoint/suspicious_reg_exe_process.yml

name: Suspicious Reg exe Process
id: a6b3ab4e-dd77-4213-95fa-fc94701995e0
version: 4
date: '2020-07-22'
author: David Dorsey, Splunk
type: Anomaly
datamodel:
- Endpoint
description: This search looks for reg.exe being launched from a command prompt not
  started by the user. When a user launches cmd.exe, the parent process is usually
  explorer.exe. This search filters out those instances.
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime FROM datamodel=Endpoint.Processes where Processes.parent_process_name
  != explorer.exe Processes.process_name =cmd.exe by Processes.user Processes.process_name
  Processes.parent_process_name Processes.dest Processes.process_id Processes.parent_process_id
  | `drop_dm_object_name("Processes")` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
  | search [| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Processes
  where Processes.parent_process_name=cmd.exe Processes.process_name= reg.exe by Processes.parent_process_id
  Processes.dest Processes.process_name | `drop_dm_object_name("Processes")` | `security_content_ctime(firstTime)`
  | `security_content_ctime(lastTime)` | rename parent_process_id as process_id |dedup
  process_id| table process_id dest] | `suspicious_reg_exe_process_filter` '
how_to_implement: You must be ingesting data that records process activity from your
  hosts to populate the Endpoint data model in the Processes node. You must also be
  ingesting logs with both the process name and command line from your endpoints.
  The command-line arguments are mapped to the "process" field in the Endpoint data
  model.
known_false_positives: It's possible for system administrators to write scripts that
  exhibit this behavior. If this is the case, the search will need to be modified
  to filter them out.
references:
- https://car.mitre.org/wiki/CAR-2013-03-001/
tags:
  analytic_story:
  - Windows Defense Evasion Tactics
  - Disabling Security Tools
  - DHS Report TA18-074A
  asset_type: Endpoint
  cis20:
  - CIS 8
  confidence: 50
  context:
  - Source:Endpoint
  - Stage:Execution
  - Stage:Initial Access
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1112/atomic_red_team/windows-sysmon.log
  impact: 70
  kill_chain_phases:
  - Actions on Objectives
  message: Suspicious $Processes.process_path.file_path$ process running with an uncommon
    parent process $Processes.parent_process_name$
  mitre_attack_id:
  - T1112
  nist:
  - DE.CM
  observable:
  - name: dest
    type: Endpoint
    role:
    - Victim
  - name: Processes.process_path.file_path
    type: File Name
    role:
    - Attacker
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Processes.parent_process_name
  - Processes.process_name
  - Processes.user
  - Processes.parent_process_name
  - Processes.dest
  - Processes.process_id
  - Processes.parent_process_id
  risk_score: 35
  security_domain: endpoint
  supported_tas:
  - Splunk_TA_microsoft_sysmon