How does this happen? This is a first ever for me?

It's probably ok. If it really was used to perform a network attack by a hacker, the hacker only used it's IP address. An IP address is a "digital address" that is assigned to every device connected to the internet. It's used like an "ID", to know who is who on the internet, so every device is assigned to an IP address to work as his ID.

The hacker could have masked his IP address by using your Xbox IP address instead, so he could not be tracked (actually he can, but it gets harder). So most likely he did not do anything to your Xbox at all, he just "masked" himself by using your Xbox "ID" so the network attack gets attributed to your Xbox instead of the hacker himself.

Don't know if you understood it, but I tried to explain it the simplest way.

If you still have any question please let me know. Also, please call your ISP and talk to them.

Usually if a hacker got control over your network, it probably did by a software installed or a URL clicked on your computer or smartphone, not by your console or a direct access to your internet connection.

You can install it on your computer and smartphone. I myself use Avast Ultimate Security (which has a Anti-Hacker and a Firewall module on it). It has some very good discounts and promotions on retailers.

You can't really install it on your console, but having it on your computer and smartphone your network should be fine.

Maybe they're wrong or maybe a hacker successfully connected to your network and made a network attack using your IP address (or your Xbox IP address).

Since Xbox connects to your network and have an IP address, the hacker could have used the Xbox IP address to make the attack. If someone hacks to your internet connection and uses your IP address, it doesn't matter if it is a console or electronic device IP address, it can be used to do anything on the internet and it will be thought that the console or eletronic device that did it.

So I really recommend you to install a good Internet Security software with Anti-Hacker and Firewall on it.

My isp says it’s my Xbox doing it?