credential_dumping_via_symlink_to_shadow_copy.yml

name: Credential Dumping via Symlink to Shadow Copy
id: c5eac648-fae0-4263-91a6-773df1f4c903
version: 3
date: '2024-05-20'
author: Patrick Bareiss, Splunk
status: production
type: TTP
description: |-
  The following analytic detects the creation of a symlink to a shadow copy, which may indicate credential dumping attempts. It leverages the Endpoint.Processes data model in Splunk to identify processes executing commands containing "mklink" and "HarddiskVolumeShadowCopy". This activity is significant because attackers often use this technique to manipulate or delete shadow copies, hindering system backup and recovery efforts. If confirmed malicious, this could prevent data restoration, complicate incident response, and lead to data loss or compromise. Analysts should review the process details, user, parent process, and any related artifacts to identify the attack source.
data_source:
- Sysmon EventID 1
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
  as lastTime from datamodel=Endpoint.Processes where `process_cmd` Processes.process=*mklink*
  Processes.process=*HarddiskVolumeShadowCopy* by Processes.dest Processes.user Processes.process_name
  Processes.process  Processes.parent_process Processes.parent_process_name Processes.original_file_name
  Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)`
  | `security_content_ctime(firstTime)`| `security_content_ctime(lastTime)` | `credential_dumping_via_symlink_to_shadow_copy_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: unknown
references:
- https://2017.zeronights.org/wp-content/uploads/materials/ZN17_Kheirkhabarov_Hunting_for_Credentials_Dumping_in_Windows_Environment.pdf
tags:
  analytic_story:
  - Credential Dumping
  asset_type: Endpoint
  confidence: 90
  impact: 90
  message: An instance of $parent_process_name$ spawning $process_name$ was identified
    on endpoint $dest$ by user $user$ attempting to create symlink to a shadow copy
    to grab credentials.
  mitre_attack_id:
  - T1003.003
  - T1003
  observable:
  - name: user
    type: User
    role:
    - Victim
  - name: dest
    type: Hostname
    role:
    - Victim
  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: 81
  security_domain: endpoint
tests:
- name: True Positive Test
  attack_data:
  - data: 
      https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1003.003/atomic_red_team/windows-sysmon.log
    source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
    sourcetype: xmlwineventlog