Hybrid worms slipping through the net...Companies' IT systems have been plagued by over seven million 'hybrid' worm attacks so far this year, with Nimda - which had an average attack rate of 3,500 per hour during the quarter - being the most widespread. Research conducted by Internet Security Systems (ISS) has found 7,665,000 instances of such 'smart' worms in the first three months of 2002, with the security specialist predicting they will continue to afflict companies over the rest of the year. The report says: "Hybrid threats, including Nimda, Code Red, and Code Blue, are especially dangerous because they combine viral payloads with multiple, automated attack scripts against common computer vulnerabilities. The attack rate for Nimda was an average of 3,500 per hour. These rates of attack remain ongoing and consistent." But David Rippon, chairman of Elite (the IT directors' forum which is part of the British Computer Society), said as long as IT departments are prepared for the worst, they have nothing to worry about. He told silicon.com: "Companies need to understand what their risks are, as not every threat will be as serious to one company as it is to another. It is useful to do some cost-benefit analysis which would consist of the risks of being attacked analysed, the possible downtime suffered and can the IT department restore and back-up as quickly as possible." Rippon also highlighted the fact that security companies are likely to predict bad news because it might generate interest in their products. "I am always a bit wary of security companies telling us the threats are on the increase. As long as you take sensible pragmatic steps, most of the threats can be avoided," he said.