Open Port Vulnerability

Question

Assume there is an open port that is not in use (maybe because a server used to use that port, but the server is not active anymore).

How can hackers use that open port in order to do their bad actions?

And how can you close such a port if you find that it's open (using nmap)?

Answer 1

Its the other way around hahaha! "Defense is the best offense"

But correct. And yeah that's how routers work is programming. You just have a nice gui. Mabey though i havent tried. If you can make a vpn, packet sniffer, and network scanner with python i don't see why you couldn't at least catch and send data to/from specific ports to the abyss

Answer 2

Please only programming related questions.

To answer: Not telling anybody "how to hack". But closing ports that are not in use is safe practice for every business that uses even the smallest network. It's called a firewall. There is firewall software (think about windows) which can block ports to a specific client machine. And you also have hardware like a meraki that filter content all throuout the network. Settings in both these options allow you to open/close ports (in general or only specific machines)

Answer 3

Slick, Ok, thanks.
Just saying: "in order to know how to defend, you must know how to attack"

So in the router's firewall settings will I be able to close ports ? And is there a way closing the ports using a programming language (python for example)?