Is it possible to leak the external IP address of a computer located on the local network?

Question

Computer networks

Many times I came across on the Internet articles-instructions for disabling WebRTC in browsers. Say, if you use VPNs, TORs, etc., then your anonymity is nevertheless at risk, since a browser with support for this technology still quietly "leaks" your real IP address. The same is possible through various plug-ins, spyware, etc. Developers of various anonymization solutions deliberately cut some features in browsers and even put the operating system inside a virtual machine to prevent IP leaks.
But I thought: if the computer is connected to the Internet through a router, is it possible to find out the IP address that it uses to surf the Internet or even the address that is assigned to it in the local network of the provider using WebRTC, spyware or something else? After all, it seems to me that only its address in the private local network, which is issued by the router, is changed to the system. Then why all these tricks? Most users have a router. I came across news that said that the FBI slipped some kind of spyware to fans of TOR and thus brought them to clean water. Did they not have a router? Or am I missing something?

Answer 1

The FBI slipped some kind of spyware on Thor lovers

If there is spyware on the workstation, then no routers will save you.

Answer 2

google in its search requests sends itself your local ip address, taken by the js script.

Answer 3

Probably you meant something else, not ip. You communicate the IP through your ISP to everyone you contact, otherwise you will not receive a response. This is an open identifier, and the first thing to start looking for. SORM will then merge your mac address and local address, and the ISP will merge your physical location. For some reason, it seems to me that when it is really needed, they will receive the primary source of information via SORM and in the TOP network, of course, encryption should put a spoke in the wheel, but who will give a guarantee. But there are still digital fingerprints of devices. So face it, if someone hasn't been taken yet, it's because they're just not interesting.

Answer 4

The router replaces all local IPs with an external
one And all Internet requests from the local area go under one external IP (well, or a couple if you have one)
Nat has such a thing on all routers for a long time included out of the box