Sample rules
GetDomainComputer with PowerShell
- source: splunk
- technicques:
- T1018
Description
The following analytic detects the execution of powershell.exe with command-line arguments that utilize Get-DomainComputer to discover remote systems. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant as Get-DomainComputer is part of PowerView, a tool often used by adversaries for domain enumeration and situational awareness. If confirmed malicious, this activity could allow attackers to map out the network, identify critical systems, and plan further attacks, potentially leading to unauthorized access and data exfiltration.
Detection logic
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name="powershell.exe") (Processes.process=*Get-DomainComputer*) by Processes.action Processes.dest Processes.original_file_name Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `getdomaincomputer_with_powershell_filter`
GetDomainController with PowerShell
- source: splunk
- technicques:
- T1018
Description
The following analytic detects the execution of powershell.exe with the Get-DomainController command, which is used to discover remote systems within a Windows domain. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. Monitoring this activity is crucial as it may indicate an attempt to enumerate domain controllers, a common tactic in Active Directory discovery. If confirmed malicious, this activity could allow attackers to gain situational awareness, potentially leading to further exploitation and lateral movement within the network.
Detection logic
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name="powershell.exe") (Processes.process=*Get-DomainController*) by Processes.action Processes.dest Processes.original_file_name Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `getdomaincontroller_with_powershell_filter`
GetDomainComputer with PowerShell Script Block
- source: splunk
- technicques:
- T1018
Description
The following analytic detects the execution of the Get-DomainComputer commandlet using PowerShell Script Block Logging (EventCode=4104). This commandlet is part of PowerView, a tool often used for enumerating domain computers within Windows environments. The detection leverages script block text analysis to identify this specific command. Monitoring this activity is crucial as it can indicate an adversary’s attempt to gather information about domain computers, which is a common step in Active Directory reconnaissance. If confirmed malicious, this activity could lead to further network enumeration and potential lateral movement within the domain.
Detection logic
`powershell` EventCode=4104 (ScriptBlockText = "*Get-DomainComputer*")
| fillnull
| stats count min(_time) as firstTime max(_time) as lastTime by dest signature signature_id user_id vendor_product EventID Guid Opcode Name Path ProcessID ScriptBlockId ScriptBlockText
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `getdomaincomputer_with_powershell_script_block_filter`
Disabled Kerberos Pre-Authentication Discovery With PowerView
- source: splunk
- technicques:
- T1558.004
Description
The following analytic detects the execution of the Get-DomainUser commandlet with the -PreauthNotRequired parameter using PowerShell Script Block Logging (EventCode=4104). This command is part of PowerView, a tool used for enumerating Windows Active Directory networks. Identifying domain accounts with Kerberos Pre-Authentication disabled is significant because adversaries can leverage this information to attempt offline password cracking. If confirmed malicious, this activity could lead to unauthorized access to domain accounts, potentially compromising sensitive information and escalating privileges within the network.
Detection logic
`powershell` EventCode=4104 (ScriptBlockText = "*Get-DomainUser*" AND ScriptBlockText="*PreauthNotRequired*")
| fillnull
| stats count min(_time) as firstTime max(_time) as lastTime by dest signature signature_id user_id vendor_product EventID Guid Opcode Name Path ProcessID ScriptBlockId ScriptBlockText
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `disabled_kerberos_pre_authentication_discovery_with_powerview_filter`