Let’s break down the DNS Amplification Attack in a clear and engaging way.

🧨 What Is a DNS Amplification Attack?

A DNS Amplification Attack is a type of Distributed Denial of Service (DDoS) attack that exploits the Domain Name System (DNS) to overwhelm a target system with massive amounts of traffic.

It’s called “amplification” because attackers use small requests to generate much larger responses, which are then directed at the victim.

🧠 How It Works

Here’s a step-by-step breakdown:

1. Spoofed Request:

   • The attacker sends a DNS query to an open DNS resolver.
   • But instead of using their own IP address, they spoof the victim’s IP address.

2. Amplified Response:

   • The DNS server responds to the query with a much larger reply (often 10–100 times bigger).
   • This response is sent to the victim’s IP address, not the attacker’s.

3. Flooding the Target:

   • The victim receives huge volumes of DNS responses from multiple DNS servers.
   • This overwhelms their network, causing slowdowns or complete outages.

📈 Why It’s So Effective

🔒 How to Defend Against It

• Disable Open DNS Resolvers: Configure DNS servers to only respond to trusted clients.
• Rate Limiting: Limit the number of requests per IP.
• Ingress Filtering: Block spoofed packets at the network edge.
• Use DNSSEC Carefully: While DNSSEC adds security, it can also increase response size—use wisely.