Data theft is one of the fastest growing cyber threats to business, according to the annual global threat report from security firm ScanSafe.
The report is based on real-time analysis of 240 billion web requests monitored by Scansafe in 2008 for corporate clients in 80 countries across five continents.
Malware increased by 5 times in 2008, but data theft Trojans increased by more than 15 times from the year before.
Data theft Trojans made up 14% of all malware blocked by Scansafe in 2008, compared with just 6% the year before.
This indicates cybercriminals are concentrating on harvesting data, with most of the malware delivered through trusted web sites enabling criminals to target specific data.
"The malware engaged in the 2008 attacks appears to be part of an unprecedented and massive data harvesting operations with sensitive verticals most at risk," the report said.
Malware is now created with criminal and commercial intent, said Mary Landesman, senior security researcher at Scansafe.
"Online crime has become a lucrative business and both commercial and personal data fetch a significant sum on black markets," she said.
Enterprises should expect an increase in intellectual property theft and illegal monitoring of all network traffic, the report said.
The report identifies the five industry sectors most targeted by data theft Trojans.
These are: Energy and Oil, Pharmaceutical and Chemical, Engineering and Construction, Transportation and Shipping, and Travel and Entertainment.
The number of unique new variants of data theft Trojans aimed at the Energy and Oil sector was nearly four times the average of 57.