An attack in which someone intercepts and co-opts an active, established session. IP spoofing is also an attack method by which IP packets are sent with a false source address, which may try to circumvent firewalls by adopting the IP address of a trusted source. This fools the firewall into thinking that the packets from the hacker are actually from a trusted source. IP spoofing can also be used simply to hide the true origin of an attack.
IP spoofing is a process where an intruder uses an IP address of another computer to acquire information or gain access. Because the intruder appears to be someone else, if a reply is sent, it goes to the spoofed address, not the intruder’s address.