The Windows SAM stores users' passwords. Restricting Remote Procedure Call (RPC) connections to the SAM to Administrators helps protect those credentials.
Set the restriction by navigating to the policy Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Network access: Restrict clients allowed to make remote calls to SAM".
Select "Edit Security" to configure the "Security descriptor:".
Add "Administrators" in "Group or user names:" if it is not already listed (this is the default).
Select "Administrators" in "Group or user names:".
Select "Allow" for "Remote Access" in "Permissions for "Administrators".
The "Security descriptor:" must be populated with "O:BAG:BAD:(A;;RC;;;BA) for the policy to be enforced.
STIG: Server - https://www.stigviewer.com/stig/windows_server_2019/2020-06-15/finding/V-93045
Desktop - https://www.stigviewer.com/stig/windows_10/2021-08-18/finding/V-220933