You can change the password of the current user (after logging in successfully) by clicking on the Settings drop-down (1) and selecting Usernames and Passwords (2) (top right corner).
Doing so will lead you to the User Administration page where you will be able to select the required user from a list of available admin users / eSS users.
Please select the required user from the list of available users. Under the Details tab select Edit to enter a new password (or use the password generator to provide random option). Please re-enter the same password into the New Password (again) field to confirm the password.
Tick the Password Expired checkbox if you would like for the user to be prompted for a password change on first login (please note: this only works for admin users and does not work for eSS users)
To lock in the changes, please click Update.
NOTE: to access the above settings, you will need to have the AccountAdmin role assigned to your user profile.