Multiple viruses spring forth in MayTop ten virus list reveals breadth of attacks

04 June 2009

BitDefender’s list of the top ten viruses in May shows that virus writers are using a number of creative techniques to take control of PCs.

Topping the list is an infection technique dubbed autorun.inf, rather than a piece of malware. The autorun.inf exploitation code technique is found in threats as diverse as Conficker and Sality and accounts for 9.93% of all detections.

Autorun.inf viruses use the Windows Autorun feature to spread. The viruses copy the autorun.inf file to the root or main directory of all the drives on your PC, internal and / or external disks, to make the virus runs every time you insert an external disk such as a USB drive or double-click the drives through Windows Explorer.

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In second place, showing how difficult viruses are to kill off is the Trojan Trojan.Clicker.CM, a popup-serving program with 9.23% of detections. The third-placed virus exploits the growing amount of video content on the web; the Wimad Trojan masquerades as a video player, with 5.34% of detections.

Polymorphic threat

Lower down in sixth place is a polymorphic file infector, which BitDefender rates as particularly dangerous. The virus infects executable (program) files an is able to reinvent itself in a number of guises in order to avoid detection. The virus installs a rootkit on the affected computer giving an attacker complete control of your computer.

Top ten viruses

BitDefender’s May 2009 Top 10 E-Threat list includes:

Trojan.AutorunINF.Gen (9.93%)
Trojan.Clicker.CM (9.23%)
Trojan.Wimad.Gen.1 (5.34%)
Exploit.SWF.Gen (4.33%)
Win32.Worm.Downadup.Gen (3.12%)
Win32.Sality.OG (2.25%)
Trojan.Exploit.ANPW (2.17%)
Dropped:Trojan.Peed.Gen (1.9%)
Trojan.Autorun.AET (1.87%)
Trojan.JS.PYV (1.73%)

Others (58.13%)

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