Name:Get DomainUser with PowerShell Script Block id:61994268-04f4-11ec-865c-acde48001122 version:5 date:2024-09-30 author:Teoderick Contreras, Mauricio Velazco, Splunk status:production type:TTP Description:The following analytic detects the execution of the `Get-DomainUser` cmdlet using PowerShell Script Block Logging (EventCode=4104). This cmdlet is part of PowerView, a tool often used for domain enumeration. The detection leverages PowerShell operational logs to identify instances where this command is executed. Monitoring this activity is crucial as it may indicate an adversary's attempt to gather information about domain users, which is a common step in Active Directory Discovery. If confirmed malicious, this activity could lead to further reconnaissance and potential exploitation of domain resources. Data_source:
-Powershell Script Block Logging 4104
search:`powershell` EventCode=4104 ScriptBlockText = "*Get-DomainUser*" | stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID | rename Computer as dest, UserID as user| `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `get_domainuser_with_powershell_script_block_filter`
how_to_implement:The following Hunting analytic requires PowerShell operational logs to be imported. Modify the powershell macro as needed to match the sourcetype or add index. This analytic is specific to 4104, or PowerShell Script Block Logging. known_false_positives:Administrators or power users may use this command for troubleshooting. References: -https://powersploit.readthedocs.io/en/latest/Recon/Get-DomainUser/ 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' - 'CISA AA23-347A' asset_type:Endpoint confidence:50 impact:50 message:Powershell process having commandline "*Get-DomainUser*" for user enumeration on $dest$ mitre_attack_id: - 'T1087.002' - 'T1087' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'EventCode' - 'Message' - 'ComputerName' - 'User' risk_score:25 security_domain:endpoint
