Windows Active Directory contains numerous objects that grant elevated access to the domain they reside in. These objects should be rarely accessed by normal users or processes. Access attempts to one or more of these objects may be evidence of attacker enumeration of Active Directory.
- Type: TTP
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2023-06-01
- Author: Steven Dick
- ID: dc2f58bc-8cd2-4e51-962a-694b963acde0
Kill Chain Phase
- CIS 10
1 2 3 4 5 6 7 `wineventlog_security` EventCode=4662 ObjectName IN ( "CN=Account Operators,*", "CN=Administrators,*", "CN=Backup Operators,*", "CN=Cert Publishers,*", "CN=Certificate Service DCOM Access,*", "CN=Domain Admins,*", "CN=Domain Controllers,*", "CN=Enterprise Admins,*", "CN=Enterprise Read-only Domain Controllers,*", "CN=Group Policy Creator Owners,*", "CN=Incoming Forest Trust Builders,*", "CN=Microsoft Exchange Servers,*", "CN=Network Configuration Operators,*", "CN=Power Users,*", "CN=Print Operators,*", "CN=Read-only Domain Controllers,*", "CN=Replicators,*", "CN=Schema Admins,*", "CN=Server Operators,*", "CN=Exchange Trusted Subsystem,*", "CN=Exchange Windows Permission,*", "CN=Organization Management,*") | rex field=ObjectName "CN\=(?<object_name>[^,]+)" | stats values(Computer) as dest, values(object_name) as object_name, dc(ObjectName) as object_count, min(_time) as firstTime, max(_time) as lastTime, count by SubjectUserName | rename SubjectUserName as user | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_ad_privileged_object_access_activity_filter`
The SPL above uses the following Macros:
windows_ad_privileged_object_access_activity_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
Enable Audit Directory Service Access via GPO and collect event code 4662. The required SACLs need to be created for the relevant objects. Be aware Splunk filters this event by default on the Windows TA.
Known False Positives
Service accounts or applications that routinely query Active Directory for information.
Associated Analytic Story
|40.0||80||50||The account $user$ accessed $object_count$ privileged AD object(s).|
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: 1