DNS rebinding is a method of manipulating resolution of domain names that is commonly used as a form of computer attack.
It can also be employed to use the victim machine for spamming, distributed denial-of-service attacks, or other malicious activities.
The server is configured to respond with a very short time to live (TTL) record, preventing the DNS response from being cached.
The malicious client-side code makes additional accesses to the original domain name (such as attacker.com).
However, when the victim's browser runs the script it makes a new DNS request for the domain, and the attacker replies with a new IP address.