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What does a DHCP do?
Dynamic Host Configuration Protocol (DHCP) is a client/server protocol that automatically provides an Internet Protocol (IP) host with its IP address and other related configuration information such as the subnet mask and default gateway.
What is DHCP spoofing attack?
DHCP spoofing occurs when an attacker attempts to respond to DHCP requests and trying to list themselves (spoofs) as the default gateway or DNS server, hence, initiating a man in the middle attack.
What are the types of DHCP attack?
Two types of DHCP attacks can be performed against a switched network: DHCP starvation attacks and DHCP spoofing. In DHCP starvation attacks, an attacker floods the DHCP server with DHCP requests to use up all the available IP addresses that the DHCP server can issue.
What is DHCP NAK packet?
The NACK message is sent to a client to indicate that the IP address that the client has requested cannot be provided by the DHCP server. This situation can occur when a client requests an invalid or duplicate address for the network.
What is DHCP offer?
DHCP Offer This message contains the network information, such as client IP address, subnet mask, default gateway IP address, DNS IP address, IP lease time and DHCP server IP address.
What do I need to know about DHCP exploitation?
This configuration usually includes, among other thing, the IP address attributed to the device, the DNS domain name and the IP address of the default router, of the DNS server and of the NetBIOS name server. This configuration, is allocated to the device only for a given time: the lease time .
How can an attacker abuse the DHCP protocol?
There are several ways the DHCP protocol can be abused: MITM attack : An attacker can spoof the DHCP server and send forged replies to the client with fake network settings allowing the attacker to intercept upcoming client’s communication.
Why is communication interrupted in a DHCP failover?
The communication interrupted state can occur due to interruption of the network link between DHCP failover partners, or it can occur because the DHCP Server service on a failover partner is unresponsive.
How does the DHCP client generate a DHCP request?
The DHCP client generates a DHCP request and broadcasts it on the network. The DHCP relay agent intercepts the broadcast DHCP request packet and inserts the relay agent information option (option 82) into the packet. The relay agent information option contains related suboptions. The DHCP relay agent unicasts the DHCP packet to the DHCP server.