Types of DDoS Attacks

DDoS attacks come in many different forms, from Smurfs to Teardrops, to Pings of Death. Below are details about the common types of attacks and amplification methods.

Attack Class: Four common categories of attacks

TCP Connection Attacks – Occupying connections

These attempt to use up all the available connections to infrastructure devices such as load-balancers, firewalls and application servers. Even devices capable of maintaining state on millions of connections can be taken down by these attacks.

Volumetric Attacks – Using up bandwidth

These attempt to consume the bandwidth either within the target network/service, or between the target network/service and the rest of the Internet. These attacks are simply about causing congestion.

Fragmentation Attacks – Pieces of packets

These send a flood of TCP or UDP fragments to a victim, overwhelming the victim’s ability to re-assemble the streams and severely reducing performance.

Application Attacks – Targeting applications

These attempt to overwhelm a specific aspect of an application or service and can be effective even with very few attacking machines generating a low traffic rate (making them difficult to detect and mitigate).

Amplification: Two ways attacks can multiply traffic they can send.

DNS Reflection – Small request, big reply.

By forging a victim’s IP address, an attacker can send small requests to a DNS server and ask it to send the victim a large reply. This allows the attacker to have every request from its botnet amplified as much as 70x in size, making it much easier to overwhelm the target.

Chargen Reflection – Steady streams of text.

Most computers and internet connected printers support an outdated testing service called Chargen, which allows someone to ask a device to reply with a stream of random characters. Chargen can be used as a means for amplifying attacks similar to DNS attacks above.

Source: Google

Posted on Nov 12, 2014 by SharkTech