Techniques
Sample rules
Windows PowerView SPN Discovery
- source: splunk
- technicques:
- T1558
- T1558.003
Description
The following analytic detects the execution of the Get-DomainUser or Get-NetUser PowerShell cmdlets with the -SPN parameter, indicating the use of PowerView for SPN discovery. It leverages PowerShell Script Block Logging (EventCode=4104) to identify these specific commands. This activity is significant as it suggests an attempt to enumerate domain accounts associated with Service Principal Names (SPNs), a common precursor to Kerberoasting attacks. If confirmed malicious, this could allow an attacker to identify and target accounts for credential theft, potentially leading to unauthorized access and privilege escalation within the network.
Detection logic
`powershell` EventCode=4104 (ScriptBlockText =*Get-NetUser* OR ScriptBlockText=*Get-DomainUser*) ScriptBlockText= *-SPN*
| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID
| rename Computer as dest
| rename UserID as user
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_powerview_spn_discovery_filter`
Windows PowerView Kerberos Service Ticket Request
- source: splunk
- technicques:
- T1558
- T1558.003
Description
The following analytic detects the execution of the Get-DomainSPNTicket commandlet, part of the PowerView tool, by leveraging PowerShell Script Block Logging (EventCode=4104). This commandlet requests Kerberos service tickets for specified service principal names (SPNs). Monitoring this activity is crucial as it can indicate attempts to perform Kerberoasting, a technique used to extract SPN account passwords via cracking tools like hashcat. If confirmed malicious, this activity could allow attackers to gain unauthorized access to sensitive accounts, potentially leading to privilege escalation and further network compromise.
Detection logic
`powershell` EventCode=4104 ScriptBlockText=*Get-DomainSPNTicket*
| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID
| rename Computer as dest
| rename UserID as user
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_powerview_kerberos_service_ticket_request_filter`