Worms & Virus types - HACKING 17 Most Dangerous Hacking Attacks (2017)

HACKING 17 Most Dangerous Hacking Attacks (2017)

Chapter 13 – Worms & Virus types


There are many different virus types, in fact, there are thousands are identified every single day, however, when it comes to worms, they seem to be a little different to standard types of viruses.

One of the reasons that worms are different then viruses is because they don’t need to be executed my a human end user. Only they would spread between networking devices by having them on, and connected to each other. They are self-replicated. Therefore worms can infect large organizations, and they can spread all over the internet too. Some types of worms can self-replicate themselves so fast that they can spread over thousands of computers just under few hours. There were some old types of worms that they have been spreading so quickly on the network that eventually created so much traffic that they have brought down the system. However most of them are silent types, and they are tough to identify, furthermore, once they have been determined on certain computers, by the time you would try to clean them up they would be spreading over to other computers, therefore giving us a hard time. Intrusion prevention systems and intrusion detection systems can help us identify and prevent them from getting on our systems.


When it comes to viruses, they would require being turned on by clicking on to be executed. Computer viruses are very similar to real viruses that humans could catch, and often a virus could be speeded from one person to another. This is what a Virus could do, however, once I virus would be executed, it would begin to infect other software, systems too. Although there are different types of viruses, could achieve different results. Some of them are similar to worms and silent types, therefore tough to identify them.

Some could cause simply slow down the performance of the computer, while the end user would blame the actual computer, however, in reality, the virus is who is responsible. Some other viruses would sit on the computer doing nothing but wait for a reboot. Once the computer would turn back on, the virus would execute itself, causing the boot process not to start, and so the computer wouldn’t turn back on. Again the end user wouldn’t know what happened, as while the computer was working there was no problem whatsoever, but when trying to proceed with a reboot, it will not occur. Let me expand on some well-known viruses with further details.


Also known as Melissa Virus, was introduced itself just at the end of the 20th Century. Melissa was spreading through an e-mail that had an important document attached. What happened is that people had to click on the attachment, and that triggered to send the same e-mail to everyone in your contact list. Therefore it was spread all over in less than a week was causing more than 70 million dollars of damage. Even that millions of computers were affected, the primary harm that caused was only on companies Servers.


The I love you Virus was another similar worm to Macro, and the technique was very similar too. Again people with curiosity were affected mostly due to the Subtitle of the e-mail: I love you. Additionally, there was an attachment that was named: Love letter for you.

Of course millions of people just had to click on the attachment as they all believed they might have a secret admirer. Unfortunately, it was another surprise instead, and that is every single file on the computer has renamed itself as: I love you, and all data become useless, including pictures, videos, music, and files at the same time. It was originated from the Philippines in 2000, infected more than 40 million computers in less than three days, causing more than 10 billion dollars of damage.

Mebroot rootkit

This piece of a virus was downloading itself without any visibility, therefore the owner did not even know there was any issue with the computer. What its job was to overwrite the computer's boot record that was telling the computer to connect to a botnet called Torpig. Torpig is also known as Sinowal or Anserin, and its primary job is to use the technique called the man in the browser. What the man in the browser does is sees everything that is being typed into the computer, therefore capturing every single keystroke, then forwarding those to botmaster. Torpig has stolen nearly half a million of credit card information just in less than a year.

SQL Slammer

This was another very dangerous computer worm that caused DoS Denial of Service as many ISP-s routers just couldn’t handle it’s traffic, causing many countries to lose internet outage.

It has infected more than 70000 victims in less than 10 minutes. It was mainly affecting Microsoft SQL Servers. Apparently, there was a patch released a half year earlier. Still, many companies didn’t find the time to implement it.

As I mentioned before, there are thousands of new viruses are identified in every day. Therefore I could go on and on about computer viruses. What you have to get from this is that each computer worm or computer virus has a different purpose, and to identify them can take time, and often only able to do it when the harm already happened.

What you can do to protect yourself is a bare minimum to have an up to date antivirus, frequently updated. Also, try to make sure that your computer is always running the latest operating system for better security against known vulnerabilities.