ARP (Address Resolution Protocol) spoofing is a type of cyber attack based on sending malicious ARP packets by attackers to the default gateway via the local network (LAN), using it in such a way as to associate its own MAC address with the IP address of the gateway device.
Typically, the goal of associating an attacker’s MAC address with another host’s IP address, such as the default gateway, is to call any traffic designed to send that IP address through an attacker. ARP spoofing permits an assailant to snap up data frames in the network and modify or stop all traffic. Usually, it is used for opening other network-based attacks, such as session hijacking attacks, MITM attacks, or denial of service.
It is important to note that only networks using ARP can use this attack. As a result, the attacker will have direct access to the network segment. In addition, ARP is indeed a commonly used protocol whose algorithms convert Internet layer addresses to the link layer.
No matter whether requested by the network host or not, any ARP replies received will be automatically cached. When it receives a new ARP reply, all records, including those that have not expired, will be overwritten. ARP protocol can not authenticate the peer from which the packet was sent because it has no method. This is the vulnerability that is possible to ARP spoofing.
ARP Spoofing Attack
Because the ARP protocol does not have authentication, this allows spoofing ARP by sending spoofed ARP messages within the local network. Such attacks will be run from an infected host in the local network or from the attacker’s device, which should be connected to the same network as the target.
The task of such an attack is to associate the attacker’s MAC address with the target host’s IP address so that all traffic going to the target host will pass through the attacker’s host.
An attacker can inspect traffic (spying) and continue sending to the target host without revealing himself, modify content before forwarding (man-in-the-middle attack), or launch an attack that partially or wholly interrupts packets transferring in the network.
Detect and Prevent ARP Spoofing
Software that specializes at detecting ARP spoofing typically uses a specific form of certification or cross-checking of ARP responses. Thus uncertified ARP responses are blocked. Typically, these methods are integrated with a DHCP server to certify dynamic and static IP addresses.
An ARP spoof attack indicator may be the presence of multiple IP addresses tied to the same MAC address, although sometimes the use of such a scheme is legitimate. The device analyzes ARP replies and sends an email notification if the ARP record is changed in a more passive approach.
How Do I Protect Myself From an ARP Spoofing attack?
👉 Don’t use Trust Relationship
Trust relationship uses IP Addresses for authentication, do not use this method. Instead, you need to create a personal login and password to identify users through security policies.
👉 Use packet Filtering
Packet filtering is the way a firewall monitors incoming and outgoing packets. It’s achieved by separating trusted internal networks from unsafe public networks. Also, a firewall can filter packages by protocol, source, and destination port numbers, or source and destination network addresses.
👉 Use Static ARP
If you have two hosts, use static ARP to add a permanent record in the cache. This will give an additional level of spoofing protection.