User Added To Highly Privileged Group
This rule detects attempts to add users to highly privileged groups on Windows systems. It specifically looks for command-line executions of 'net localgroup <groupname> /add' or 'Add-LocalGroupMember -Group <groupname>' where the group name is either 'Group Policy Creator Owners' or 'Schema Admins'. These groups are considered highly privileged, and unauthorized additions could indicate privilege escalation or persistence.
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