What are the types of flooding attacks? Full analysis of common attack methods

in the digital age, cyber security threats emerge one after another. As a common means of network attacks, flooding attacks have become the first choice for many attackers due to their low implementation cost and strong destructive power. Such attacks consume the target's bandwidth, memory, CPU and other resources by sending massive invalid requests or data to the target system, making it impossible to provide services to legitimate users. This article will deeply dissect the various common types of flooding attacks, analyze their operation logic and harm, and help readers establish a clearer understanding of cyber security.

What are the common flooding attacks at the network layer?

network layer is the basic link of data transmission and one of the main targets of flooding attacks, which directly target the vulnerabilities of network protocols.

1, ICMP flood attack

ICMP flood attack, also known as ping flood attack, the attacker will send a large number of ICMP echo request packets to the target server. Normally, the server will reply with echo response packets after receiving the request, but when the request volume far exceeds the server's processing limit, the server's bandwidth and CPU resources will be quickly exhausted, and thus unable to respond to legitimate users' network requests. This type of flood attack is often used to attack small websites or personal servers, and the implementation threshold is low.

2, Smurf flood attack

Smurf flood attack with the aid of broadcast network amplification attack effect, the attacker will forge the source Internet Protocol Address ICMP request packet sent to the target network broadcast address, all hosts in the network will receive the request and reply to the forged source Internet Protocol Address packets, and the source Internet Protocol Address is the target of the attacker. The final target will receive a large number of reply packets, instantly overwhelmed by traffic, belonging to the prototype of a typical distributed flood attack.

2. Analysis of typical flooding attack types in the transport layer

transport layer is responsible for end-to-end data transmission control, and the characteristics of TCP and UDP protocols make it a key breakthrough direction for flooding attacks.

1, SYN flood attack

SYN flood attack exploits the vulnerability of TCP three-way handshake to launch an attack. The attacker sends a large number of fake source IP SYN request packets to the target server. After the server receives the request, it will reply SYN + ACK packets and wait for the ACK packets of the source IP to complete the handshake. However, because the source IP is forged, the server can never receive the ACK packet, and can only maintain a half-connection state. A large number of half-connections will quickly consume the server's connection resources, resulting in legitimate users unable to establish normal connections. This kind of flood attack is a classic attack method against the transport layer, with a wide range of harm.

2, UDP flooding attack

UDP is a connectionless protocol, which can send data without establishing a connection. Attackers take advantage of this feature to send massive UDP data packets to random ports of the target server. After the server receives the data packet, it will try to process it, but because most of the data packets are invalid, the server will continue to consume resources to parse these useless data, and eventually be paralyzed due to resource exhaustion. UDP flooding attacks are often used to attack services that rely on the UDP protocol, such as streaming media servers and DNS servers.

III. Inventory of high-incidence flooding attack methods in the application layer

the application layer directly docking user services, flooding attacks launched for specific application characteristics, higher accuracy and concealment.

1, HTTP flooding attack

HTTP flood attack by sending a large number of legitimate HTTP requests to the target Web server, such as frequent page refresh, submit forms, etc., consume the server's application layer resources. Unlike other flood attacks, the requests of this type of attack are in a legal format, which is difficult to identify through simple traffic filtering. Attackers often use botnets to launch distributed HTTP flood attacks, which can paralyze large e-commerce websites and government platforms in a short time.

2, DNS flooding attacks

DNS flood attack is launched for domain name resolution service. The attacker sends a large number of domain name resolution requests to the target DNS server. The server needs to constantly query the domain name records and reply to the results. A large number of invalid requests will exhaust the server's resolution resources, resulting in legitimate users not being able to resolve the domain name normally, and then unable to access the corresponding website. Such flooding attacks will directly affect the availability of domain name services and deal a huge blow to network services that rely on domain name access.

4. Why are distributed flooding attacks more destructive?

with the improvement of cyber security protection technology, the effect of single node flooding attack is gradually limited, distributed flooding attack came into being, and the destructive power increased geometrically.

1, DDoS flooding attacks

DDoS flood attack is Distributed Denial-of-service, the attacker controls a large number of infected zombie hosts, forms a botnet, and launches a flood attack on the target at the same time. Because the attack traffic comes from multiple different Internet Protocol Addresses, the target server is difficult to defend through IP blocking. Massive distributed traffic will instantly exhaust all the resources of the target, and even paralyze the server cluster of large enterprises. It is one of the most harmful flood attack types.

2, P2P flooding attacks

P2P flooding attacks are launched by means of the characteristics of peer-to-peer networks. Attackers use the node propagation ability of P2P networks to distribute attack tasks to a large number of P2P nodes, which simultaneously send attack traffic to the target. This type of flooding attack has more scattered traffic sources and is more difficult to defend. It is often used to attack medium-sized enterprise websites with certain protection capabilities.

sum up, flooding attacks cover multiple levels such as network layer, transmission layer, application layer, etc., from single node attacks to distributed coordinated attacks, with diverse types and destructive power. By understanding the principles and methods of various flooding attacks, we can more accurately identify cyber security threats, lay the foundation for subsequent development of targeted protection strategies, and effectively improve the security and stability of our own network environment.