DDoS technique using DNS servers to multiply attack traffic and overwhelm victims.
DNS amplification is a DDoS technique that exploits open DNS resolvers to multiply attack traffic. Attackers send DNS queries with spoofed source addresses (the victim's IP) to open DNS servers. The DNS servers send responses—much larger than the queries—to the victim. Because responses are amplified (sometimes 50x larger than queries), attackers generate massive traffic volumes with minimal resources. DNS amplification is one of several amplification attacks exploiting UDP-based protocols.
Why It Matters
The DSC Perspective:
DNS amplification demonstrates why DDoS mitigation requires specialised services—your bandwidth simply can't absorb amplified attacks. It also explains why organisations shouldn't run open DNS resolvers.