name: Clop Common Exec Parameter
id: 5a8a2a72-8322-11eb-9ee9-acde48001122
version: 2
date: '2023-03-17'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytics are designed to identifies some CLOP ransomware
  variant that using arguments to execute its main code or feature of its code. In
  this variant if the parameter is "runrun", CLOP ransomware will try to encrypt files
  in network shares and if it is "temp.dat", it will try to read from some stream
  pipe or file start encrypting files within the infected local machines. This technique
  can be also identified as an anti-sandbox technique to make its code non-responsive
  since it is waiting for some parameter to execute properly.
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 Processes.process_name != "*temp.dat*"
  Processes.process = "*runrun*" OR Processes.process = "*temp.dat*" 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)` | `clop_common_exec_parameter_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: Operators can execute third party tools using these parameters.
references:
- https://www.mandiant.com/resources/fin11-email-campaigns-precursor-for-ransomware-data-theft
- https://blog.virustotal.com/2020/11/keep-your-friends-close-keep-ransomware.html
tags:
  analytic_story:
  - Clop Ransomware
  asset_type: Endpoint
  confidence: 100
  impact: 100
  message: An instance of $parent_process_name$ spawning $process_name$ was identified
    on endpoint $dest$ by user $user$ attempting using arguments to execute its main
    code or feature of its code related to Clop ransomware.
  mitre_attack_id:
  - T1204
  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_name
  - Processes.parent_process
  - Processes.original_file_name
  - Processes.process_name
  - Processes.process
  - Processes.process_id
  - Processes.parent_process_path
  - Processes.process_path
  - Processes.parent_process_id
  risk_score: 100
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/clop/clop_b/windows-sysmon.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: xmlwineventlog