How to DDoS?

Understanding how a DDoS (Distributed Denial of Service) Attack is initiated can help you better defend against it. 

How a DDoS Attack is Typically Launched?

The common DDoS attack process typically includes the following stages:

1. Reconnaissance and Target Selection: Attackers first conduct reconnaissance to collect information about potential targets, including website traffic, server performance, network architecture, etc. Based on the collected information, attackers choose one or more vulnerable targets.
2. Building a Botnet: Attackers infect a large number of computers or devices with malware or other means, turning them into part of a botnet. These infected devices can be controlled by attackers to carry out various malicious activities, including DDoS attacks.
3. Attack Planning and Preparation: Attackers choose the appropriate attack type and strategy based on the target's characteristics and network environment. Attackers may test the target's defense capabilities to determine the best time and method for the attack.
4. Launching a DDoS Attack: Attackers send a large number of requests to the target through the botnet, attempting to exhaust its resources. Common DDoS attack types include SYN Flood, UDP Flood, ICMP Flood, HTTP Flood, etc.
5. Monitoring and Adjustment: During the attack, attackers monitor the attack's effectiveness and adjust their strategies based on the target's response. Attackers may use IP spoofing to confuse tracking or launch attacks from multiple vectors simultaneously.
6. Attack Conclusion and Retreat: When the attack achieves the desired effect or is thwarted by defense systems, attackers stop the attack and retreat.Attackers may destroy evidence or leave backdoors for future attacks.
7. Analyzing Attack Results: After the attack, attackers may analyze the results to assess the effectiveness of the attack and their own technical capabilities.Attackers may also share their attack experiences with other hackers or sell attack services on the dark web.

What are the Common Types of DDoS attacks?

DDoS attacks come in various types, each targeting different layers of a network. Here are some common types of DDoS attacks:

Application Layer Attacks

• HTTP Flood: Attackers send a large number of HTTP GET or POST requests, attempting to exhaust server resources.
• Slowloris: Opens a large number of half-open HTTP connections, gradually consuming server connection resources.
• Low and Slow Attacks: Sends seemingly legitimate but extremely slow HTTP requests to avoid detection.

Protocol Attacks

• SYN Flood: Sends a large number of SYN requests without completing the three-way handshake process, causing server resources to be exhausted.
• Smurf Attack: Uses IP broadcasting and ICMP echo requests to amplify traffic and direct it towards the victim.
• Ping of Death: Sends specially crafted ICMP Echo Request packets larger than 65,535 bytes, attempting to crash the target system.

DNS Amplification/Reflection Attacks

• Attackers forge the victim's IP address and send query requests to open DNS servers. The DNS servers respond to these requests, sending a large amount of data to the victim's IP address.

Volumetric Attacks

• UDP Flood: Sends a large number of UDP packets to the target server, occupying bandwidth and preventing legitimate traffic.
• ICMP Flood: Sends a large number of ICMP Echo Request (Ping) packets, consuming network bandwidth.
• Fragmentation Attack: Sends specially crafted fragmented packets, causing the target system to exhaust resources while reassembling packets.

Connection Exhaustion Attacks

• Establishes a large number of TCP connections, exhausting the target server's connection pool resources.

Application Layer Specific Attacks

• Targeting specific vulnerabilities or features of an application, such as database query attacks, XML entity expansion, etc.

Hybrid Attacks

• Combines multiple attack types to increase the complexity and effectiveness of the attack.

What are Commonly Used DoS and DDoS Attack Tools?

Attackers use several common DDoS tools to launch Distributed Denial of Service attacks. Some of these tools include:

• LOIC (Low Orbit Ion Cannon): LOIC is an open-source network stress testing and DoS attack application. It generates a large volume of network traffic to overwhelm the target server or network. LOIC can be used by individual attackers or as part of a coordinated botnet.
• HOIC (High Orbit Ion Cannon): HOIC is an upgraded version of LOIC, designed to generate a more significant volume of network traffic. It allows attackers to use multiple simultaneous connections and target multiple URLs, making it more challenging to defend against.
• Slowloris: Slowloris is a DDoS tool that targets web servers by opening and maintaining many simultaneous connections, slowly sending partial HTTP requests. This method consumes server resources and eventually causes the server to become unresponsive without generating a high volume of network traffic.
• Hping: Hping is a command-line utility that can be used to generate custom TCP/IP packets for network auditing and testing. In the hands of an attacker, hping can be used to launch DDoS attacks by sending a large number of packets to the target server.
• NTP Amplification: This type of DDoS attack exploits vulnerabilities in the Network Time Protocol (NTP) to amplify the volume of traffic sent to the target server. Attackers send small NTP requests with a spoofed IP address (the target's IP address) to NTP servers, which then send a much larger response to the target, overwhelming its resources.
• Mirai: Mirai is a malware that targets Internet of Things (IoT) devices and turns them into a botnet to launch DDoS attacks. The Mirai botnet has been responsible for some of the largest DDoS attacks in history.

How to Defend Against DDoS Attacks?

To defend against DDoS attacks, organizations should adopt various security measures. Here are some common defensive measures:

• DDoS Protection Services: Use services like Tencent EdgeOne, Cloudflare, Akamai, or AWS Shield to filter and mitigate attack traffic.
• Network Architecture: Implement distributed network architecture and load balancing to spread traffic across multiple servers.
• Real-Time Monitoring: Use real-time traffic monitoring to detect and respond to unusual traffic patterns.
• Firewalls and IDS: Configure firewalls and intrusion detection systems to identify and block malicious traffic.
• Rate Limiting: Implement rate limiting to control the number of requests a user can make to your server.

Conclusion

Protect your web and internet-facing services from DDoS attacks with Tencent EdgeOne. EdgeOne provides the following robust features:

1. Comprehensive DDoS Protection: Tencent Cloud EdgeOne offers a comprehensive, efficient, and professional service for DDoS attack prevention, ensuring security and safety for your business. It provides protection against various types of DDoS attacks, ranging from the network layer to the application layer.
2. Basic DDoS Protection: EdgeOne enables platform-level basic DDoS protection by default. This service monitors network traffic in real-time and immediately cleans up traffic-based DDoS attacks when detected, providing second-level protection. The default security policies are based on attack profiles, behavior pattern analysis, AI intelligent recognition, and other protection algorithms, effectively dealing with common DDoS attack behaviors.
3. Web Protection: In addition to DDoS protection, EdgeOne also provides web protection. It identifies good access requests from bad ones and protects your origin server against web attacks such as SQL injection, XSS attacks, and local file inclusion in real-time. These protections are powered by Tencent's self-developed AI engine and its vast threat intelligence database, enabling accurate and effective identification and blocking mechanisms.

By using Tencent EdgeOne DDos Protection, businesses can ensure the availability and performance of their online services, even in the face of large-scale DDoS attacks. We have now launched a free trial, welcome to contact us for more information.