Computing reports that November was the worst month for malware since records began in the mid-1980s, according to antivirus firm Sophos.
The company detected 1,940 new pieces of malware in the past month, and has seen a 48 per cent increase in threats over the year.
The bulk of the new threats are not self-propagating viruses such as worms, but Trojan software that either logs the user's behaviour or allows remote control of their PC.
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.
While all of the top ten threats are Windows-based worms, the Register reports the number of Trojan horses written during 2005 outweighs worms by a ratio of two-to-one.