Windows Network Share Interaction With Net

Original Source: [splunk source]
Name:Windows Network Share Interaction With Net
id:4dc3951f-b3f8-4f46-b412-76a483f72277
version:3
date:2024-11-26
author:Dean Luxton
status:production
type:TTP
Description:This analytic detects network share discovery and collection activities performed on Windows systems using the Net command. Attackers often use network share discovery to identify accessible shared resources within a network, which can be a precursor to privilege escalation or data exfiltration. By monitoring Windows Event Logs for the usage of the Net command to list and interact with network shares, this detection helps identify potential reconnaissance and collection activities.
Data_source:
  • -Sysmon EventID 1
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(Processes.user_category) as user_category values(Processes.user_bunit) as user_bunit FROM datamodel=Endpoint.Processes WHERE `process_net` BY Processes.user Processes.dest Processes.process_exec Processes.parent_process_exec Processes.process Processes.parent_process
| `drop_dm_object_name(Processes)`
| regex process="net[\s\.ex1]+view|net[\s\.ex1]+share|net[\s\.ex1]+use\s"
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_network_share_interaction_with_net_filter`


how_to_implement:The detection is based on data originating from either Endpoint Detection and Response (EDR) telemetry or EventCode 4688 with process command line logging enabled. These sources provide security-related telemetry from the endpoints. To implement this search, you must ingest logs that contain the process name, parent process, and complete command-line executions. These logs must be mapped to the Splunk Common Information Model (CIM) to normalize the field names capture the data within the datamodel schema.
known_false_positives:Unknown
References:
  -https://attack.mitre.org/techniques/T1135/
drilldown_searches:
name:'View the detection results for - "$dest$" and "$user$"'
search:'%original_detection_search% | search dest = "$dest$" user = "$user$"'
earliest_offset:'$info_min_time$'
latest_offset:'$info_max_time$'
name:'View risk events for the last 7 days for - "$dest$" and "$user$"'
search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$", "$user$") starthoursago=168 | 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:'$info_min_time$'
latest_offset:'$info_max_time$'
tags:
  analytic_story:
    - 'Active Directory Discovery'
    - 'Active Directory Privilege Escalation'
    - 'Network Discovery'
  asset_type:Endpoint
  atomic_guid:
    - 'ab39a04f-0c93-4540-9ff2-83f862c385ae'
  confidence:100
  impact:20
  message:User $user$ leveraged net.exe on $dest$ to interact with network shares, executed by parent process $parent_process$
  mitre_attack_id:
    - 'T1135'
    - 'T1039'
  required_fields:
    - 'Processes.process_name'
    - 'Processes.user'
    - 'Processes.dest'
    - 'Processes.process_exec'
    - 'Processes.parent_process_exec'
    - 'Processes.process'
    - 'Processes.parent_process'
  observable:
    name:'dest'
    type:'Hostname'
    - role:
      - 'Victim'
    name:'user'
    type:'User'
    - role:
      - 'Victim'
  product:
    - 'Splunk Enterprise'
    - 'Splunk Enterprise Security'
    - 'Splunk Cloud'
  risk_score:20
  security_domain:endpoint

tests:
name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1135/net_share/windows-sysmon.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None