The following analytic utilizes PowerShell Script Block Logging (EventCode=4104) to identify the execution of the
Get-AdGUser commandlet. The
Get-AdUser commandlet is used to return a list of all domain users. Red Teams and adversaries may leverage this commandlet to enumerate domain groups for situational awareness and Active Directory Discovery.
- Type: Hunting
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2022-09-13
- Author: Teoderick Contreras, Mauricio Velazco, Splunk
- ID: 21432e40-04f4-11ec-b7e6-acde48001122
Kill Chain Phase
- CIS 10
1 2 3 4 5 6 `powershell` EventCode=4104 ScriptBlockText = "*get-aduser*" ScriptBlockText = "*-filter*" | 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_aduser_with_powershell_script_block_filter`
The SPL above uses the following Macros:
get_aduser_with_powershell_script_block_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
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.
Associated Analytic Story
|25.0||50||50||Powershell process having commandline "get-aduser" for user enumeration on $dest$|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 2