High Quality Content by WIKIPEDIA articles! ARP spoofing, also known as ARP cache poisoning or ARP poison routing (APR), is a technique used to attack a local-area network (LAN). ARP spoofing may allow an attacker to intercept data frames on a LAN, modify the traffic, or stop the traffic altogether. The attack can only be used on networks that make use of the Address Resolution Protocol (ARP) and not another method of address resolution.