Avast gives a warning that my router password is insufficient/insecure. I’m running Ethernet, no wifi network on. I don’t know that any password is required to use Ethernet. Ideas about what’s happening here? Thanks!
It may be the router log in password for changing router setup
This means that the box that is connecting you to the internet (the router) might have too weak password for configuring it. This puts you in risk, even an innocent-looking page might be running a script that will connect from your PC to the router, guess its password (provided it is really weak) and then modify the settings there - like changing your DNS server to something you would really hate.
Even worse if you are still using the default router login password that came with the router out of the box.
It is important to protect your router by changing its admin password to a unique stong password to help protect your device.