Affected software version 1.1.26 and up
If your users are imported via LDAP, you won't need to change anything on the appliance. Just go to your Active Directory and change the user password. If, however, you have local users that have not been imported via LDAP, you can follow these instructions to change the password.
Once you're logged in to the appliance web interface go to the Admin menu.
Once you're in the Admin menu section go to User Management on the left, find the user you want to change the password for on the list and select him/her.
You'll see the Password and Repeat password fields. Just enter the new password here and click Save.