The 11 September terrorist attacks on the US, however, have not prompted any obvious cyber attacks, ISS concluded.
Overall, Internet security has been undermined by a steady tide of denial of service (DoS) attacks, as well as the rise of hybrid attacks - attack tools that spread through multiple means, such as the Web, e-mail, file sharing and instant messaging, ISS wrote. Worms such as Code Red and Nimda are leading examples of hybrid threats, though there have since been others.
"Internet risk will continue to increase as long as fundamental Internet risk factors are not lessened in some way," ISS wrote. "Attacks are now global in scope and round the clock in incidence."
The company compiled its data from more than 350 high-volume intrusion detection sensors it manages around the world.
One major risk factor that will be difficult to address is the way the majority of attacks are being perpetrated. Almost 70% of attacks in the first quarter of 2002, were launched on server port 80, the same port that carries Web traffic, ISS said. This poses a particular problem because curtailing access to port 80 would also hit Web traffic, the company wrote.
However, companies can take steps to reduce their vulnerabilities to port 80, including turning off unused services, such as Web server software on a file server, ISS wrote.
"Since almost 70% of malicious activity occurs as a result of entry through port 80, it is obvious and imperative that firewalls should be augmented with additional intrusion and defense technology, since firewalls cannot prevent this form of unauthorised access in their own right," the company wrote.
"There's no such thing as low threat [level] on the Internet," said Dennis Treece, director of the X-Force Special Operations Group at ISS. "If you're going to connect to it, you better have a suit of armour."
The volume of attacks against port 80 is "troubling because it's the wide-open door", Treece added. Many businesses that lack IT expertise have seen firewalls as silver bullets in the past because of their ability to block traffic, but as most firewalls allow connections on port 80, this data shows that firewalls are being marginalised, he said.
The Nimda worm, which infected hundreds of thousands of computers in September 2001, is still widespread on the Internet, ISS wrote, despite there being a patch available from Microsoft to block it. Nimda is "a dominant, expensive and enduring threat", ISS concluded.
Despite multiple warnings on the potential for cyber terrorist attacks after 11 September, ISS did not see any indications of such attacks.
"The events of 11 September had no apparent effect on malicious Internet activity, but interest in security was up. So far, there have been no cyber attacks that we can relate directly to the physical attacks of11 September," the company wrote.
ISS also counted 537 new security vulnerabilities in software for the quarter. Security vulnerabilities, and slowness to apply patches to fix those holes, have resulted in a number of serious security incidents, including the Code Red and Nimda worms.
"The software community, including developers, vendors and users, is beginning to raise the profile of security within the development process. Improvements, however, will take time," ISS said. "As a result, the medium and long-term risk assessment for the Internet remains significantly less than optimistic, with hybrid threats continuing as the most dangerous form of attack."