name: Detect Renamed RClone
id: 6dca1124-b3ec-11eb-9328-acde48001122
version: 2
date: '2021-09-16'
author: Michael Haag, Splunk
status: production
type: Hunting
description: The following analytic identifies the usage of `rclone.exe`, renamed,
  being used to exfiltrate data to a remote destination. RClone has been used by multiple
  ransomware groups to exfiltrate data. In many instances, it will be downloaded from
  the legitimate site and executed accordingly. During triage, isolate the endpoint
  and begin to review parallel processes for additional behavior. At this stage, the
  adversary may have staged data to be exfiltrated.
data_source:
- Sysmon Event ID 1
search:
  selection1:
    Image|endswith: rclone.exe
    OriginalFileName: rclone.exe
  condition: (selection1)
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. In addition,
  confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
  endpoint product.
known_false_positives: False positives should be limited as this analytic identifies
  renamed instances of `rclone.exe`. Filter as needed if there is a legitimate business
  use case.
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/
tags:
  analytic_story:
  - DarkSide Ransomware
  - Ransomware
  asset_type: Endpoint
  confidence: 90
  impact: 30
  message: The following $process_name$ has been identified as renamed, spawning from
    $parent_process_name$ on $dest$ by $user$.
  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
  risk_score: 27
  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