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Another category adapted to fit the new malware dynamic by creating massive botnets.

Worms? What are they?

Worms are programs that make copies of themselves in different places on a computer. The objective of this type of malware is usually to saturate computers and networks, preventing them from being used. Unlike viruses, worms don’t infect files.

What do they do?

The main objective of worms is to spread and infect as many computers as possible. They do this by creating copies of themselves on infected computers, which then spread to other computers by several channels including email, P2P programs and instant messaging, among others.

Worms often use social engineering techniques. To do so, malware creators use attractive names to camouflage the malicious files. Most of these names relate to sex, famous people, pirate software, current affairs or generally try to appeal to people’s morbid curiosity.

The use of these techniques significantly increases around dates such as Valentine’s Day, Christmas and Halloween.

Evolution of Worms

Worms have also been adapted to fit the new malware dynamic. Previously, worms were designed largely to achieve notoriety for the creators, and were therefore programmed to spread massively and infect computers around the world.

Now, however, worms are more geared towards generating financial gain. They are used to create massive botnets which control thousands of computers around the world. Cyber-crooks then send commands to these computers (zombies) to send spam, launch denial of service attacks, download malicious files, etc. Conficker or The Gaobot or Sdbot  families are just a few examples of this type of worm. In the following statistics you can check out the importance of this type of malware nowadays:

At present, there are thousands upon thousands of computers being used as zombies without their owners realizing. These compromised computers can still be used normally, and so often the only indication of the infection is reduced performance.

How can you protect yourself from Worms?

There are a series of basic measures that users can take to ensure that computers are protected against worms:

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