The Domain Name System (DNS) is a hierarchical naming system that is built on a distributed database for computers, services, or any other resource connected to the Internet or a private network. It translates the domain names meaningful to humans into the numerical identifiers associated with the networking equipment for the purpose of locating and addressing these devices worldwide[1]. The job of a DNS is to convert the human readable addresses entered on the address bar of the browser into machine readable IP addresses. DNS spoofing is a term that refers to the action of answering a DNS request that was intended for another server (a ?real? DNS server). This arrangement can be in a server-server exchange (a DNS server asks another for a mapping) or in a client-server dialog (when a client asks a DNS server for a mapping). In the last many years, several security flaws have been discovered in the protocol and its specific implementations. This research paper gives an overview over the different threats to the DNS and their attack targets. We have discussed the various DNS Spoofing Attacks without IP Spoofing and DNS Spoofing Attacks with IP Spoofing and discuss their success chances and possible countermeasures. Finally, as a case study, DNS spoofing attack model is constructed and the availability of the attacked system is evaluated. The proposed approach can be used for other kinds of attacks and other types of systems, networks and applications.

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Dns Spoofing Attacks It-security Dns