The number of malware detections in 2006 increased 172 per cent from 2005, according to research by vendor PandaLabs .

Massive infections caused by a single virus have practically disappeared to be replaced by multiple variants now silently infect computers, says the firm's report.

'Users have a false sense of security, believing there are no dangerous threats. The truth is, however, that there is now more malware than ever. PandaLabs detected the same amount of malware last year as in the previous fifteen years combined,' said Luis Corrons, technical director at PandaLabs.

Hybrid malware was an increasing trend in 2006 and will continue in 2007. The fusion between worms and rootkits is an example of how in the future it will be more difficult to distinguish between different malware families, according to PandaLabs.

Trojans have now become the most popular type of malware, largely because they spread without notice and are therefore ideal for targeted attacks, the report says.

Regarding spyware, or more specifically adware, the report underlines how widely it is now distributed due in part to the fact that these programs conceal themselves as part of other legitimate programs and that users do not consider them dangerous. Adware creators are therefore exploiting the situation and reaping the benefits.

The report also stresses the changes in the way bots are being used.

'As firewalls evolve and port monitoring improves, bot herders are having to control their creations using alternative means, such as P2P networks,' said Corrons.

The use of worms as a means of propagation for other malware is another trend confirmed by PandaLabs in 2006.

The motivation of cyber-crooks during 2006 was once again financial. In this sense, the sale of malware online flourished last year, according to PandaLabs. It is now possible on the Internet to buy any number of malicious tools, from kits for creating phishing web pages to vulnerability exploits or services for creating Trojans, meaning malware will continue to rise.