According to a report published recently by researchers at the University of Michigan's Electrical Engineering and Computer Science Department and network security company Arbor Networks, antivirus products are inconsistent at best when it comes to identifying attacks such as worms, phishing and botnets.

"Using a large, recent collection of malware that spans a variety of attack vectors (such as spyware, worms, spam), we show that different AV products characterise malware in ways that are inconsistent across AV products, incomplete across malware, and that fail to be concise in their semantics," the report claims.

The report shows that host-based antivirus techniques failed to "detect or provide labels for between 20 and 62 percent of the malware samples".