Detect RClone Command-Line Usage

name: Detect RClone Command-Line Usage
id: 32e0baea-b3f1-11eb-a2ce-acde48001122
version: 19
creation_date: '2021-05-13'
modification_date: '2026-05-13'
author: Michael Haag, Splunk
status: production
type: TTP
description: The following analytic detects the usage of `rclone.exe` with specific command-line arguments indicative of file transfer activities. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and process details. This activity is significant as `rclone.exe` is often used by adversaries for data exfiltration, especially during ransomware attacks. If confirmed malicious, this behavior could lead to unauthorized data transfer, resulting in data breaches and potential loss of sensitive information. Immediate isolation of the affected endpoint and further investigation are recommended.
data_source:
    - Sysmon EventID 1
    - Windows Event Log Security 4688
    - CrowdStrike ProcessRollup2
    - Cisco Network Visibility Module Flow Data
search: |
    | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
    as lastTime from datamodel=Endpoint.Processes where
    (Processes.original_file_name="rclone.exe" OR Processes.process_name="rclone.exe")
    Processes.process IN (
            "*copy*", "*mega*", "*pcloud*", "*ftp*",
            "*--config*", "*--progress*", "*--no-check-certificate*",
            "*--ignore-existing*", "*--auto-confirm*", "*--transfers*",
            "*--multi-thread-streams*"
            )
    by Processes.action Processes.dest Processes.original_file_name Processes.parent_process
    Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id
    Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec
    Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level
    Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
    | `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/
drilldown_searches:
    - name: View the detection results for - "$user$" and "$dest$"
      search: '%original_detection_search% | search  user = "$user$" dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$" and "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
finding:
    title: 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.
    entity:
        field: user
        type: user
        score: 50
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 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.
threat_objects:
    - field: parent_process_name
      type: parent_process_name
    - field: process_name
      type: process_name
analytic_story:
    - Storm-0501 Ransomware
    - Hellcat Ransomware
    - DarkSide Ransomware
    - Ransomware
    - Black Basta Ransomware
    - Cactus Ransomware
    - Cisco Network Visibility Module Analytics
asset_type: Endpoint
mitre_attack_id:
    - T1020
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test - Sysmon
      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
      test_type: unit
    - name: True Positive Test - Cisco NVM
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/cisco_network_visibility_module/cisco_nvm_flowdata/nvm_flowdata.log
          source: not_applicable
          sourcetype: cisco:nvm:flowdata
      test_type: unit