In the "DNS attack prevention popular science series" of previous lecture, we introduce the common DNS attacks, and to prevent DDoS attacks, methods to protect the safety of the operation. Today we bring is to guard against DNS cache poisoning attacks. First, let's say it is "DNS cache poisoning."
DNS cache poisoning Introduction
Cache poisoning (DNS cache poisoning), also known as DNS cache pollution (DNS cache pollution), refers to the number deliberately created (poisoning) or unintentionally Manufacturing (pollution) out of the DNS packet, so that the DNS cache server cache the wrong DNS record.
DNS cache poisoning works is: As usual DNS queries without any authentication mechanism, and are usually based on the DNS query protocol UDP is a connectionless unreliable, so the DNS queries are vulnerable to tampering, by DNS UDP port 53 on the request query listen, and once found matching the keyword is immediately disguised as a target domain name resolution services