ARP Spoofing / ARP Poisoning

Summary

ARP Spoofing, also known as ARP Poisoning, is a network attack technique where an attacker sends falsified Address Resolution Protocol (ARP) messages to a local network. This manipulates the ARP cache of devices, associating the attacker’s MAC address with the IP address of a legitimate device, enabling interception, modification, or disruption of network traffic.

Key Characteristics

• Exploits the lack of authentication in the ARP protocol.
• Allows attackers to perform man-in-the-middle (MITM) attacks.
• Can lead to data interception, session hijacking, or denial of service.
• Targets local area networks (LANs) where ARP is used for IP-to-MAC address resolution.
• Often used to redirect traffic through the attacker’s device without detection.

Defensive Controls

• Implement static ARP entries for critical devices to prevent unauthorized updates.
• Use Dynamic ARP Inspection (DAI) on network switches to validate ARP packets.
• Deploy network segmentation and VLANs to limit attack scope.
• Enable encryption protocols such as HTTPS, SSH, and VPNs to protect data in transit.
• Monitor network traffic for unusual ARP activity or duplicate IP addresses.

Related Security Solutions

Network security appliances and intrusion detection systems (IDS) often include ARP spoofing detection capabilities. Managed switches with Dynamic ARP Inspection and endpoint security tools can help mitigate ARP poisoning attacks. Additionally, secure communication protocols and network access control (NAC) solutions complement defenses against ARP spoofing.