Windows XP/2000/NT/ME/98/95

Fizzer is a dangerous worm, as it is programmed to capture the keystrokes entered in the affected computer and save them in a text file.

Fizzer also acts as a backdoor type Trojan, allowing a hacker to gain remote access to the resources of the affected computer.

Fizzer also contains instructions for ending process active in memory, which mainly belong to antivirus programs. 

This worm mainly spreads via e-mail. It sends a copy of itself to all the contacts it finds in the Outlook and Windows Address Books. Fizzer also spreads through the P2P (peer-to-peer) file sharing program KaZaA.

Fizzer is difficult to recognize, as it does not display any warnings or messages that indicate that it has infected a computer.