In order to be able to commit crimes in cyberspace, including stealing bank data, receiving income from calls to expensive paid phone numbers or demanding ransom, cybercriminals create and distribute network worms, many of which have caused serious epidemics on the Internet.

Massive computer virus attacks

Cybercriminals vary their methods of delivering computer viruses according to their goals. Cybercriminals often seek to install Trojan programs on as many computers as possible. Examples of such worms from the recent past:

Mydoom

Bagle

Warezov – mail worm

Limiting the spread of computer virus attacks

In some cases, instead of trying to infect the maximum number of computers with viruses, cybercriminals may intentionally limit their number. This approach allows criminals to avoid too much publicity, as well as excessive attention from law enforcement agencies.

To limit the number of infections, criminals refuse to use uncontrolled network worms. Instead, they can use websites infected with Trojan programs. Criminals can track the number of visitors to a website and limit the number of computers attacked by a Trojan program.