name: Clop Common Exec Parameter
id: 5a8a2a72-8322-11eb-9ee9-acde48001122
version: 1
date: '2021-03-17'
author: Teoderick Contreras, Splunk
type: TTP
datamodel:
- Endpoint
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.
search: '| tstats `security_content_summariesonly` values(Processes.process) as cmdline
  values(Processes.parent_process_name) as parent_process values(Processes.process_name)
  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.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: 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: 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
  confidence: 100
  context:
  - Source:Endpoint
  - Stage:Execution
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/clop/clop_b/windows-sysmon.log
  impact: 100
  kill_chain_phases:
  - Exploitation
  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
  supported_tas:
  - Splunk_TA_microsoft_sysmon
  asset_type: Endpoint