yep , i agree with the most parts. the telnet client is disabled by default on windows 10 , but usually on the Router/Access points that have this feature , its enabled by default and thats why you get this notification in eset >>
In order to deal with this issue you have to disable that feature from the web interface of your device AKA "modem settings" .
but here`s the problem . when you connect a new device like a router etc , Eset Firewall blocks it by default . specially when you try to change the settings in your router web interface for which it require running certain scripts and those also will get blocked in your Firewall , etc .
So in order to do this the easiest way would be to disconnect from the internet , then disable your Eset Firewall , and only then go to your router settings otherwise you have to unlock the required Devices , ports , and services manually everytime you want to change your settings which might not go smooth as u think everytime. here are some examples of the Firewall blocking attempts for your device to be connected to your Pc>>