name: Detect RClone Command-Line Usage
id: 32e0baea-b3f1-11eb-a2ce-acde48001122
version: 1
date: '2021-05-13'
author: Michael Haag, Splunk
type: batch
datamodel:
- Endpoint
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.
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where 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.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: To successfully implement this search you need to be ingesting information
  on process that include the name of the process responsible for the changes from
  your endpoints into the `Endpoint` datamodel in the `Processes` node.
known_false_positives: There is potential for false positives as these arguments may
  be used by other applications. Filter or tune the analytic as needed.
references:
- https://redcanary.com/blog/rclone-mega-extortion/
- https://www.fireeye.com/blog/threat-research/2021/05/shining-a-light-on-darkside-ransomware-operations.html
- https://thedfirreport.com/2021/03/29/sodinokibi-aka-revil-ransomware/
tags:
  analytic_story:
  - DarkSide Ransomware
  - Ransomware
  automated_detection_testing: passed
  confidence: 70
  context:
  - Source:Endpoint
  - Stage:Exfiltration
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1020/windows-sysmon.log
  impact: 50
  kill_chain_phases:
  - Exfiltration
  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: Parent 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
  risk_score: 35
  security_domain: endpoint