In June and for the third month running, Klez.I tops the list of the most virulent malicious code, compiled from the results of the free online virus scanner, Panda ActiveScan. Klez.I is a rapidly-spreading e-mail worm that sends itself out to all addresses in the affected computer's address book and has variable message texts and subject fields. It can also change the apparent e-mail address of the sender to give the impression that it has been sent from an address other than that of the infected computer. This worm also exploits a known vulnerability in Internet Explorer which allows the infected file to run automatically when the message is viewed in the preview pane.

Klez.I accounted for almost 20 percent of all incidents recorded in June. Following far behind in reported incidents were Elkern.C, Help, Sircam, Klez.F and Bck/SubSeven, each being responsible for less than five percent of attacks. Hybris and Nimda also appeared in June, but at a much lower percentage than previous months. Rounding out the Top Ten were Disemboweler and Kazoa.

+ W32/Klez.I 19.07%
+ W32/Elkern 4.84%
+ VBS/Help 3.43%
+ W32/Sircam 2.91%
+ W32/Klez.F 2.88%
+ Bck/SubSeven 2.13%
+ W32/Hybris 1.87%
+ W32/Nimda 1.74%
+ W32/Disemboweler 1.74%
+ W32/Kazoa 1.66%

To help users keep their computers safe from virus attacks, Panda Software offers Panda ActiveScan, free of charge at http://www.pandasecurity.com/Disinfect.asp?ID=5. Panda ActiveScan is updated daily, offering protection against even the latest generation viruses.

Panda Software also reminds users that ActiveScan is available to webmasters who want to include it on their websites. Their visitors will therefore be provided the means to ensure their systems are safe from viruses, thus enhancing website appeal. Administrators can request the HTML code at http://www.pandasecurity.com/activescan-for-websites.htm.