PandaLabs revealed that almost six percent (5.77 percent) of the two million computers they scanned showed an infection by the malicious Conficker worm. The worm, which originated in China, has now extended across 83 countries, and is particularly virulent in the United States, Spain, Taiwan, Brazil and Mexico. In the U.S. alone, PandaLabs has identified at least 18,000 infected computers, although the real figure could be much higher.

On Jan. 12, PandaLabs issued an orange alert, cautioning users to be wary of this worm that propagates itself through USB memory devices such as USB Drives or MP3 players. In investigating Conficker further, PandaLabs' researchers have also discovered that some variants are launching brute force attacks to extract passwords from infected computers and from internal networks in companies. The frequency of weak passwords (common words, own names, etc.) has aided the distribution of this worm. By harvesting passwords, cyber-crooks can access computers and use them maliciously.

This worm also uses an innovative system of social engineering to spread via USB devices: in the Windows options menu that appears when inserting a USB device, it has disguised the option to run the program (activating the malware) as the option to open the folder to see the files, so when users simply want to see the contents of a memory stick, they will actually be running the worm and infecting their computers.