Name:GetWmiObject User Account with PowerShell Script Block id:640b0eda-0429-11ec-accd-acde48001122 version:4 date:2024-10-17 author:Mauricio Velazco, Splunk status:production type:Hunting Description:The following analytic detects the execution of the `Get-WmiObject` commandlet with the `Win32_UserAccount` parameter via PowerShell Script Block Logging (EventCode=4104). This method leverages script block text to identify when a list of all local users is being enumerated. This activity is significant as it may indicate an adversary or Red Team operation attempting to gather user information for situational awareness and Active Directory discovery. If confirmed malicious, this could lead to further reconnaissance, privilege escalation, or lateral movement within the network. Data_source:
-Powershell Script Block Logging 4104
search:`powershell` EventCode=4104 (ScriptBlockText="*Get-WmiObject*" AND ScriptBlockText="*Win32_UserAccount*") | stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID | `security_content_ctime(firstTime)` | `getwmiobject_user_account_with_powershell_script_block_filter`
how_to_implement:To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup here https://docs.splunk.com/Documentation/UBA/5.0.4.1/GetDataIn/AddPowerShell#Configure_module_logging_for_PowerShell. known_false_positives:Administrators or power users may use this PowerShell commandlet for troubleshooting. References: -https://attack.mitre.org/techniques/T1087/001/ -https://www.splunk.com/en_us/blog/security/hunting-for-malicious-powershell-using-script-block-logging.html drilldown_searches:
: tags: analytic_story: - 'Winter Vivern' - 'Active Directory Discovery' - 'Malicious PowerShell' asset_type:Endpoint confidence:50 impact:30 message:Local user discovery enumeration using PowerShell on $Computer$ by $UserID$ mitre_attack_id: - 'T1087' - 'T1087.001' - 'T1059.001' observable: name:'Computer' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'EventCode' - 'ScriptBlockText' - 'Computer' - 'UserID' risk_score:15 security_domain:endpoint
