Windows Create Local Administrator Account Via Net

Original Source: [splunk source]
Name:Windows Create Local Administrator Account Via Net
id:2c568c34-bb57-4b43-9d75-19c605b98e70
version:3
date:2025-02-10
author:Bhavin Patel, Splunk
status:production
type:Anomaly
Description:The following analytic detects the creation of a local administrator account using the "net.exe" command. It leverages Endpoint Detection and Response (EDR) data to identify processes named "net.exe" with the "/add" parameter and keywords related to administrator accounts. This activity is significant as it may indicate an attacker attempting to gain persistent access or escalate privileges. If confirmed malicious, this could lead to unauthorized access, data theft, or further system compromise. Review the process details, user context, and related artifacts to determine the legitimacy of the activity.
Data_source:
  • -Sysmon EventID 1
  • -Windows Event Log Security 4688
  • -CrowdStrike ProcessRollup2
search:| tstats `security_content_summariesonly` count values(Processes.user) as user values(Processes.parent_process) as parent_process values(parent_process_name) as parent_process_name min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_net` AND Processes.process=*/add* AND Processes.process IN ("*administrators*", "*administratoren*", "*administrateurs*", "*administrador*", "*amministratori*", "*administratorer*", "*Rendszergazda*", "*Администратор*", "*Administratör*") by Processes.process Processes.process_name Processes.parent_process_name Processes.dest Processes.user| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_create_local_administrator_account_via_net_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:Administrators often leverage net.exe to create admin accounts.
References:
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 ("$user$", "$dest$") 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:
    - 'DHS Report TA18-074A'
    - 'Azorult'
    - 'CISA AA22-257A'
    - 'DarkGate Malware'
    - 'CISA AA24-241A'
  asset_type:Endpoint
  mitre_attack_id:
    - 'T1136.001'
  product:
    - 'Splunk Enterprise'
    - 'Splunk Enterprise Security'
    - 'Splunk Cloud'
  security_domain:endpoint

tests:
name:'True Positive Test'
 attack_data:
  data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1136.001/atomic_red_team/windows-sysmon.log
  source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
  sourcetype: XmlWinEventLog
manual_test:None