How Distributed Denial-Of-Service (DDoS) Attacks Work

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Learn about cybersecurity


In our previous article, we briefly discussed the following 7 modern cyber attacks:

  • Ransomware
  • WannaCry
  • NotPetya
  • SimpleLocker
  • TeslaCrypt
  • CryptoLocker
  • PC Cyborg

In this article, we move on explaining what a Distributed Denial-of-Service is and in what ways a Distributed Denial of Service attack are more detrimental than traditional Denial of Service.


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Distributed denial-of-service (DDoS) attacks

A DDoS attack is a malicious attempt to disrupt the legitimate user traffic of a server by overwhelming it with a flood of random traffic. DDoS differs from DoS by its distributed nature, attacking a target from several independent networks of compromised systems. These compromised computer systems are called bots, and a botnet refers to a group of such bots under the control of the same malicious actor.

DDoS attacks have become a frequent hazard, as they are commonly used to take revenge, conduct extortion, activism, and even for cyberwar. In October 2016, leading ISP Dyn's DNS was bombarded by a wave of DNS queries from millions of bots. The attack was executed by the Mirai botnet, and was composed of over 100,000 IoT devices.


From script kiddies to geopolitical

There are numerous theories about the attack launched on October 26, 2016 on Dyn's DNS infrastructure. One of the most sensitive and highest impact DDoS attacks was noted to be against Dyn, a US-based DNS service provider that caused several major websites including Twitter, Reddit, GitHub, Amazon, Netflix, PayPal, and many more to be inaccessible by a major part of country. There are numerous theories and claims as to who could be behind this. Security researchers pointed the finger of blame at script kiddies; however, there was also a claim by a hacker group, Jester, that the Russian government was behind the attacks. The hacker group Jester defaced the Russian foreign ministry against a Democratic National Committee (DNC) hack.

This didn't just stop there; there have been some high-profile damages as of late as well. The political crisis in Qatar led to a DDoS attack on Al Jazeera's website. France's presidential election was disrupted by attacks on the Le Figaro and Le Monde websites.


Ease of launching a DDoS attack

You could launch DDoS attacks by paying $10 an hour, $200, or $600-$1200 for an entire week. Several attackers on the dark web are offering DDoS for hire services that make launching DDoS attacks easy.

Someone who is looking to bombard their targets with a burst of heavy traffic gets charged for every second of botnet use rather than an hourly fee.


Top targeted countries

Attackers can compromise a computer and make their own bot. These bots are used to conduct reconnaissance, web page crawl, and even DDoS attacks. It is important to understand that countries that have a larger number of compromised systems should be aware of their global risk index.

This article is written in collaboration with Rajneesh Gupta.

Advanced persistence threat

In our next article, we will continue our cybersecurity journey by discussing what are advanced persistence threats and how they work.

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