DNS hijacking - Definition from the Hotspot Shield Glossary

DNS Hijacking is the process of altering the resolution of a DNS query (Domain Name System). DNS servers are used to translate a website address (Domain Name) into an IP address in order for users to connect to it.

This process can be hijacked and the DNS server altered in order to redirect information to a different source, or to display a different website than is intended. DNS Hijacking is a prime method used by phishing scams where a user thinks they are visiting a proper website, but in fact that website has had its DNS record altered and the user is redirected to a fake version of that website. There have been many instances where ISP providers have actively practiced DNS Hijacking in order to collect user data or push certain advertisements. Rogue DNS servers are used in DNS Hijacking and are considered DNS servers that have been compromised by hackers and can be used to change the DNS records of a website.