A Worm is a virus-like software application which spreads itself to other computers. Worms send themselves out to email addresses collected from the infected PC. Worms are known to mutate and they usually carry a destructive payload.
This keylogger can not be stopped by firewall, because the firewall sees it as a part of the browser. That's why it is a serious threat for users privacy. It can also change the homepage and monitor user's actions. The prime function is logging keystrokes, including passwords and bank accounts and sending them to hacker.
