Name:Disabled Kerberos Pre-Authentication Discovery With PowerView id:b0b34e2c-90de-11ec-baeb-acde48001122 version:5 date:2024-09-30 author:Mauricio Velazco, Splunk status:production type:TTP 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. Data_source:
-Powershell Script Block Logging 4104
search:`powershell` EventCode=4104 (ScriptBlockText = "*Get-DomainUser*" AND ScriptBlockText="*PreauthNotRequired*") | stats count min(_time) as firstTime max(_time) as lastTime by Opcode Computer UserID EventCode ScriptBlockText | rename Computer as dest | `security_content_ctime(firstTime)` | `disabled_kerberos_pre_authentication_discovery_with_powerview_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 PowerView for troubleshooting References: -https://attack.mitre.org/techniques/T1558/004/ -https://m0chan.github.io/2019/07/31/How-To-Attack-Kerberos-101.html -https://stealthbits.com/blog/cracking-active-directory-passwords-with-as-rep-roasting/ drilldown_searches: name:'View the detection results for - "$dest$"' search:'%original_detection_search% | search dest = "$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") 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 Kerberos Attacks' asset_type:Endpoint confidence:90 impact:60 message:Disabled Kerberos Pre-Authentication Discovery With PowerView from $dest$ mitre_attack_id: - 'T1558' - 'T1558.004' observable: name:'dest' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'ScriptBlockText' - 'Opcode' - 'Computer' - 'UserID' - 'EventCode' risk_score:54 security_domain:endpoint
