VirusBuster, the Hungary-based specialist of IT security continuously monitors virus occur-rence and activity. Data from VirusBuster´s mail protection systems – in-house and exter-nally deployed alike – is collected and processed. VirusBuster uses the results to generate monthly statistics of the most frequent infections. These monthly virus toplists are published on the company's website as well

How was the catch in October? ”Like in previous months, our toplist was dominated by tro-jan malware. Some of them distribute fake antivirus programs, while others connect the victim´s PC into a botnet. The only new color on October´s palette was Trojan.DR.Snag, a trojan harvesting the CD keys of popular computer games”, commented the results Gábor Szappanos, the head of VirusBuster´s virus lab.

Trojans are malicious programs, which got their name from the legendary wooden horse built by the Greeks to defeat Troy: They pretend to serve users, but in fact they are designed to cheat their victims. Many trojans set off (fake) alarm bells warning the user of a virus infection, and then download a rogue antivirus application. The downloaded program promises to clean the machine, but, in reality, either does nothing (the better option), or starts some malicious activity. The user is often charged for such a download, so these trojans are, in fact, tools for fraud. They mostly come in e-mail attachments. Spammers disguise them as some useful file, such as an order confirmation. Opening the attachment, however, launches the infection mechanism.

Botnets (short for robot networks) are networks of unknowing victim PCs (called zombies) controlled by hackers. Users should get rid of botnet malware as soon as possible, since oth-erwise they may become accomplices in the cybercriminals´ activities, warned Gábor Szap-panos."

Source: VirusBuster