Membership in the Group Policy Creator Owners and Incoming Forest Trust Builders groups must be limited.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-243487	SRG-OS-000480	AD.0240	SV-243487r959010_rule	2024-09-13	3

Description
Membership in the Group Policy Creator Owners and Incoming Forest Trust Builders groups assigns a high privilege level for AD functions. Unnecessary membership increases the risk from compromise or unintended updates. Members of these groups must specifically require those privileges and be documented.

ℹ️ Check
Start "Active Directory Users and Computers" (Available from various menus or run "dsa.msc"). Review the membership of the "Incoming Forest Trust Builders" group. Navigate to the "Built-in" container. Right-click on the "Incoming Forest Trust Builders", select "Properties" and then the "Members" tab. If any accounts are not documented as necessary with the ISSO, this is a finding. Review the membership of the "Group Policy Creator Owner" group. Navigate to the "Users" container. Right-click on the "Group Policy Creator Owner", select "Properties" and then the "Members" tab. If any accounts are not documented as necessary with the ISSO, this is a finding. It is possible to move some system-defined groups from their default locations. If a group is not in the location noted, review other containers to locate.

ℹ️ Check

Start "Active Directory Users and Computers" (Available from various menus or run "dsa.msc"). Review the membership of the "Incoming Forest Trust Builders" group. Navigate to the "Built-in" container. Right-click on the "Incoming Forest Trust Builders", select "Properties" and then the "Members" tab. If any accounts are not documented as necessary with the ISSO, this is a finding. Review the membership of the "Group Policy Creator Owner" group. Navigate to the "Users" container. Right-click on the "Group Policy Creator Owner", select "Properties" and then the "Members" tab. If any accounts are not documented as necessary with the ISSO, this is a finding. It is possible to move some system-defined groups from their default locations. If a group is not in the location noted, review other containers to locate.

✔️ Fix
Document membership of the Group Policy Creator Owners and Incoming Forest Trust Builders groups. Remove any accounts that do not require the privileges these groups assign.