the objective here is to exhaust the ARP table or cache capacity preventing hosts, servers or network nodes from storing previously ARP resolution results. For every packet to be transmitted a new resolution must be triggered and responded to which increases control traffic, number of packet drops, and processor resources.
the attacker here alters the content of the ARP packet itself: IP or MAC information. It intercepts and uses reply and request packets instead of gratuitous ARP mechanism for this purpose.
Other attacks may focus on the IP packet itself or by exploiting vulnerabilities of certain layer 2 protocols: