Ask HN: How can a hacker buy 25,000 IP addresses? 6 years ago
I think if you are tracking or getting the IP address from a UDP packet, hacker can fake it. But if it is TCP, they cannot fake it since TCP handshake need to communicate back and forth with origin of the connection which in this case is the hacker.
IP address are cheap these days with IPv6 available. Are those IPv4 or IPv6?