ARP Toxin is a simple Perl script designed to ARP poison a host on the LAN. It uses Nemesis as a packet crafting tool to create and send the ARP packets. It is NOT original code, merely a slightly improved version of the sample arpredirect script from the book “Hacking: The Art of Exploitation”. This variant allows one to set their own poisoning interval and interface to poison on.
You can download it from the following link: https://packetstormsecurity.com/files/download/107327/arptoxin.txt
Source: https://packetstormsecurity.com/files/107327/ARP-Toxin-Cache-Poisoner.html