splunk-security_content/detections/endpoint/detect_rclone_command_line_usage.yml

name: Detect RClone Command-Line Usage
id: 32e0baea-b3f1-11eb-a2ce-acde48001122
version: 2
date: '2021-11-29'
author: Michael Haag, Splunk
status: production
type: TTP
description: This analytic identifies commonly used command-line arguments used by
  `rclone.exe` to initiate a file transfer. Some arguments were negated as they are
  specific to the configuration used by adversaries. In particular, an adversary may
  list the files or directories of the remote file share using `ls` or `lsd`, which
  is not indicative of malicious behavior. During triage, at this stage of a ransomware
  event, exfiltration is about to occur or has already. Isolate the endpoint and continue
  investigating by review file modifications and parallel processes.
data_source:
- Sysmon Event ID 1
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where `process_rclone` Processes.process
  IN ("*copy*", "*mega*", "*pcloud*", "*ftp*", "*--config*", "*--progress*", "*--no-check-certificate*",
  "*--ignore-existing*", "*--auto-confirm*", "*--transfers*", "*--multi-thread-streams*")  by
  Processes.dest Processes.user Processes.parent_process Processes.parent_process_name Processes.process_name Processes.process
  Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)`
  | `security_content_ctime(firstTime)` |  `security_content_ctime(lastTime)` | `detect_rclone_command_line_usage_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: False positives should be limited as this is restricted to
  the Rclone process name. Filter or tune the analytic as needed.
references:
- https://redcanary.com/blog/rclone-mega-extortion/
- https://www.mandiant.com/resources/shining-a-light-on-darkside-ransomware-operations
- https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
- https://thedfirreport.com/2021/11/29/continuing-the-bazar-ransomware-story/
tags:
  analytic_story:
  - DarkSide Ransomware
  - Ransomware
  asset_type: Endpoint
  confidence: 70
  impact: 50
  message: An instance of $parent_process_name$ spawning $process_name$ was identified
    on endpoint $dest$ by user $user$ attempting to connect to a remote cloud service
    to move files or folders.
  mitre_attack_id:
  - T1020
  observable:
  - name: user
    type: User
    role:
    - Victim
  - name: dest
    type: Hostname
    role:
    - Victim
  - name: parent_process_name
    type: Process
    role:
    - Parent Process
  - name: process_name
    type: Process
    role:
    - Child Process
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Processes.dest
  - Processes.user
  - Processes.parent_process
  - Processes.process_name
  - Processes.process
  - Processes.process_id
  - Processes.parent_process_id
  - Processes.original_file_name
  risk_score: 35
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1020/windows-sysmon.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: xmlwineventlog