UnsecureJoin specifies whether to add the computer to the domain without requiring a unique password.
UnsecureJoin is performed, by using a null session with a pre-existing account. This means there is no authentication to the domain controller when configuring the machine account; it is done anonymously. The account must have a well-known password or a specified value for MachinePassword. The well-known password is the first 14 characters of the computer name in lower case. For more information, see MachinePassword. If the well-known password is used, then the password is changed to a strong password by Netlogon after the join completes.
For the list of the supported Windows editions and architectures that this component supports, see Microsoft-Windows-UnattendedJoin.
The following XML output shows the computer added to the domain without the requirement of a unique password.