Webmin is included in the FileWave appliances to allow you to easily configure the system. This is only relevant if you run a FileWave server yourself. For customers who have their server hosted by FileWave you do not need to worry about these steps.
The first important thing is to not allow any traffic to TCP 10000 on your server except from networks you will connect to it from. There is no reason to expose this port to the Internet. The second item is to be sure you change the root password on your appliance from the default. This is mentioned in https://fwkb.atlassian.net/wiki/spaces/evalguides/pages/2228270 but this step is very important.
If there is no IP address specified because DHCP is not available on the subnet for your FileWave Linux Appliance, log in with the username "root" with the password "filewave".
Run "nmtui" at the command prompt to launch the Network Manager Text UI so you can configure the networking for the FileWave VM appliance. You'll need to reload the IP stack with "service network restart". Skip the network configuration steps later in the Webmin.
Browse to this URL and log in with username "root" and password "filewave".
Go to System > Change Passwords on the left and select the "root" account on the right from the list of usernames. Enter a new root password, confirm it, and click Change. Note that this will change the default password for the root account used to log into the server from "filewave" to whatever you choose so enter a secure password that is easy for you to remember, but it should be a long and complex password or you should take steps to configure SSH to only allow connections with a certificate. The FileWave server is a full Linux OS and can be managed like any other.