Let’s break down what an ICMP Flood is in the context of computer networks and cybersecurity.

🌊 What Is an ICMP Flood?

An ICMP Flood is a type of Denial-of-Service (DoS) attack that targets a computer or network by overwhelming it with ICMP packets, typically ping requests.

🧠 Understanding the Components

🔹 ICMP (Internet Control Message Protocol)

• A network protocol used for diagnostic and error-reporting purposes.
• Commonly used by the ping command to check if a host is reachable.

🔹 Ping Requests

• A small ICMP packet sent to a target to measure response time and connectivity.
• The target replies with a “pong” (echo reply).

🚨 How an ICMP Flood Works

• The attacker sends a massive number of ICMP Echo Request packets to the target.
• The target system tries to respond to each request, consuming CPU, memory, and bandwidth.
• If the flood is large enough, the target becomes slow, unresponsive, or crashes.

🎯 Targets and Impact

🛡️ How to Mitigate ICMP Floods

• Rate Limiting: Restrict the number of ICMP packets allowed per second.
• Firewall Rules: Block or filter ICMP traffic from suspicious sources.
• Intrusion Detection Systems (IDS): Detect and alert on abnormal ICMP activity.
• Anti-DDoS Services: Use cloud-based protection to absorb and filter attacks.

🧪 Real-World Example

Imagine a website hosted on a server. If an attacker sends thousands of ping requests per second, the server might spend all its resources replying to pings instead of serving web pages—making the site inaccessible to real users.