If you are looking for default credentials for Open-AudIT, you can find them @ Information about default users and passwords
SSH/Linux Users
NMIS Web Users
Open-AudIT Web Users
To change the Unix passwords, type
man passwd
To change the Web Users passwords, if you have not integrated Apache with another form of Authentication, it will be using the default method which are users defined in a file managed with htpasswd.
The default installation location for NMIS8 is /usr/local/nmis8, it may be installed somewhere else, adjust the commands accordingly
cd /usr/local/nmis8/conf
htpasswd users.dat <username>
Start the VM, and Centos V4 should boot to a login screen.
Login as root, the password is documented on the VM Description tab.
Username: root
Password administrator
Username: nmis
Password: nmis@nmis