Click Settings of the realm for which the password has to be changed. The Security > realm screen comprising of the Groups, Permissions, Login Module, and User Manager details appears.
Click All Users under Groups to enter the Security > Realm > Users screen.
Click Settings for the user for whom the password is to be changed. The Edit Settings (user) screen is displayed.
Enter the old and new passwords.
Re-enter the new password to confirm and click Save. The password gets changed and should be used from the next login.
Note: In both the cases, the user name appears by default.