Systems and methods for blocking spoofed traffic

A system for use in blocking spoofed traffic within communications networks, the system comprising:

• a computing system comprising at least one processor and a memory, the memory comprising instructions that, when executed by the at least one processor, cause the at least one processor to:
• obtain routing information for an autonomous system of a communications network, the routing information identifying Internet Protocol (IP) addresses associated with the autonomous system;
• in response to receiving the routing information, generate a prefix list based on the routing information, the prefix list including one or more prefixes encompassing the IP addresses identified by the routing information;
• and
• transmit, to a network device of the communications network, first instructions configured to cause the network device to update a filter function of the network device based on the prefix list such that the network device permits network traffic that originates from IP addresses within the prefixes of the prefix list.