PandaLabs has detected the appearance of Cisum.A, a worm whose most distinguishing characteristic is that it insults the user by displaying "YOU ARE AN IDIOT" on screen, while playing an MP3 audio file that repeats the same phrase.

Cisum.A can only spread automatically across computer networks. If a network user runs the file carrying Cisum.A, this worm copies itself under the name ProjectX.exe to the root directory of the shared drives on the computer.

The malware also ends the processes belonging to antivirus programs and other IT security applications, leaving the computer vulnerable to attack from other viruses or hackers. It creates several entries in the Windows Registry in order to ensure that it is run whenever the computer starts up.

Even though no incidents caused by this worm have been registered, Panda Software advises users to take precautions with any file they receive or download from the Internet and to update their antivirus software.