DHCP attack definition
A DHCP attack, also called DHCP spoofing, happens when a malicious actor intercepts or disrupts communication between devices on a network and the DHCP server. The Dynamic Host Configuration Protocol (DHCP) assigns IP addresses to devices on a network. In a DHCP attack, the hacker attempts to control this process, usually to distribute false IP addresses or reroute network traffic.
See also: network security protocols, email spoofing, website spoofing, DNS redirection
DHCP attack examples
- Malicious network control: A hacker could distribute false IP addresses to control network traffic and direct it through their system, facilitating data theft.
- Denial of service: By flooding a DHCP server with requests, a hacker could render the server unavailable, preventing legitimate devices from connecting to the network.
Comparing a DHCP attack with similar attacks
DHCP attacks share similarities with ARP spoofing attacks. Both techniques involve a hacker impersonating a legitimate network entity to intercept or manipulate traffic. However, while ARP spoofing focuses on linking IP addresses to the wrong MAC addresses, DHCP attacks primarily aim to control IP address allocation.
Advantages and disadvantages of DHCP attack (from the perspective of a malicious actor)
Pros:
- Ease of implementation: DHCP attacks require only a basic understanding of network protocols and readily available tools.
- Potential for data theft: Intercepting network traffic can yield valuable information.
Cons:
- Network security measures: Many networks have defenses in place that can detect and block DHCP attacks.
- Legal consequences: Unauthorized network intrusion is illegal and punishable by law.
Preventing DHCP attacks
- Use DHCP snooping: This network security feature monitors DHCP traffic, blocking suspicious activity.
- Implement dynamic ARP inspection (DAI): DAI validates ARP packets in a network, preventing IP address spoofing.
