Nearly 16,000 new viruses, worms and Trojans have appeared in 2005, but criminals are moving their focus to niche targeted groups with specially customised malware to steal data and cash.

The huge increase in the number of malware programs stems from the activities of criminal gangs intent on using trojans, worms and viruses to make a profit, according to a new report from anti-virus software firm Sophos, entitled the Security Threat Management Report 2005.

These gangs have been focusing their efforts on a smaller number of victims, who are targeted with customised malware, so that the creators of the virus can evade the attentions of anti-virus software vendors and security providers.

"Internet criminals may be turning their back on large scale attacks not only because they do not wish to draw attention to their efforts, but also because they cannot practically handle the amount of stolen data they might receive if they infected hundreds of thousands of computers in one day," the report noted.

A report published in November 2005 by Financial Insights, an IDC company, estimated that global financial institutions lost USD400 million in 2004 due to phishing schemes. Phishing is a system whereby scammers send an email, purporting to be from their financial institution, which induces them to reveal their online banking details.

Instead of going for the large financial institutions, cyber criminals are now engaging in what has been dubbed "puddle phishing", where they target a smaller financial institution that may only have a few branches.

Another phishing phenomenon is the "spear phishing" practice, where attackers will target employees in a specific company in an attempt to gain passwords and usernames to access confidential data.

Because these attacks are so targeted, the most dangerous viruses are unlikely to be included among the top-10 most common viruses, which anti-virus vendors issue to raise security awareness among internet users.

While all of the top ten threats are Windows-based worms, the number of Trojan horses written during 2005 outweighs worms by a ratio of two-to-one.

In 2005, the Zafi-D virus has topped the Sophos list as the most prevalent virus on the internet. The most prevalent virus in 2004, Netsky-P, has dropped to second place this year. Sober-Z - which was only unleashed in November 2005 - has already climbed to third place as it continues to disrupt and clog networks worldwide.

The other viruses in the top 10 were Sober-N, Zafi-B, Mytob-BE, Mytob-AS, Netsky-D, Mytob-GH, Mytob-EP.

Copyright © 2005, ENN (http://www.enn.ie/)

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