A DNS Amplification Attack is a type of DDoS (denial-of-service) attack that exploits the functionality of open DNS resolvers to overwhelm a target server or network with an amplified amount of traffic, rendering it inaccessible.
The attacker sends small queries with spoofed IP addresses to open DNS resolvers, which then send large responses to the target server or network. The target receives an amplification of the attacker’s initial traffic, and its network becomes clogged with the spurious traffic, causing a denial-of-service.
Some ways to prevent or mitigate DNS Amplification Attacks are:
• Restricting access to open DNS resolvers by using firewall rules, whitelists, or authentication mechanisms.
• Implementing rate limiting or throttling on DNS resolvers to limit the number of queries per second from a single source.
• Deploying anti-spoofing techniques such as ingress filtering or BCP 38 to prevent attackers from using forged IP addresses.
• Using DNSSEC (DNS Security Extensions) to validate the authenticity and integrity of DNS responses.
• Using DDoS protection services or solutions that can detect and filter out malicious traffic before it reaches the target server or network.
