linux_change_file_owner_to_root.yml

name: Linux Change File Owner To Root
id: c1400ea2-6257-11ec-ad49-acde48001122
version: 1
date: '2021-12-21'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: This analytic looks for a commandline that change the file owner to root
  using chown utility tool. This technique is commonly abuse by adversaries, malware
  author and red teamers to escalate privilege to the targeted or compromised host
  by changing the owner of their malicious file to root. This event is not so common
  in corporate network except from the administrator doing normal task that needs
  high privilege.
data_source:
- Sysmon for Linux EventID 1
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where (Processes.process_name = chown
  OR Processes.process = "*chown *") AND Processes.process = "* root *" by Processes.dest
  Processes.user Processes.parent_process_name Processes.process_name Processes.process
  Processes.process_id Processes.parent_process_id Processes.process_guid | `drop_dm_object_name(Processes)`
  | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `linux_change_file_owner_to_root_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: Administrator or network operator can execute this command.
  Please update the filter macros to remove false positives.
references:
- https://unix.stackexchange.com/questions/101073/how-to-change-permissions-from-root-user-to-all-users
- https://askubuntu.com/questions/617850/changing-from-user-to-superuser
tags:
  analytic_story:
  - Linux Privilege Escalation
  - Linux Persistence Techniques
  - Linux Living Off The Land
  asset_type: Endpoint
  confidence: 80
  impact: 80
  message: A commandline $process$ that may change ownership to root on $dest$
  mitre_attack_id:
  - T1222.002
  - T1222
  observable:
  - name: dest
    type: Hostname
    role:
    - Victim
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Processes.dest
  - Processes.user
  - Processes.parent_process_name
  - Processes.process_name
  - Processes.process
  - Processes.process_id
  - Processes.parent_process_id
  risk_score: 64
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548.001/chmod_uid/sysmon_linux.log
    source: Syslog:Linux-Sysmon/Operational
    sourcetype: sysmon_linux