Ubuntu Live CD root password and live session password for user Ubuntu

sudo passwd ubuntu

Then create your password, you will need to already be in Terminal

To create a usable root user’s account on a live cd, you can set the root password then su. This has not been possible in previous versions of Ubuntu as their user model made you remember to sudo before each command requiring root access.

sudo passwd root

As of Ubuntu 9.10, I haven’t been able to login with “demo” or “Ubuntu” as the password for live session username “Ubuntu”.