IE8 best at blocking malware sites, says study

The two bottom browsers, Opera 9.64 and IE7, were essentially useless at stopping their users from visiting bad sites, catching just 5% and 4%, respectively. "[They] provided virtually no protection against malware," said the NSS report.

Microsoft was the sole sponsor of the test, Moy acknowledged, adding that having just one funding source was unusual for his company. "It wasn't exactly a comfortable feeling, but I think it was all pretty above board. They were very hands off."

Even though Gartner Inc. analyst John Pescatore noted that NSS has a solid reputation in testing circles, he cautioned against reading too much into the report. "You do have to look at the results of this with a jaundiced eye," he said Tuesday.

Pescatore also questioned whether the numbers reflected how browsers -- and more importantly, browser users -- really work. "For IE7 and Firefox, in real-world use, we don't see any major difference in their security performance," he said. "If you look at how Firefox 3.0 is really used, and how IE8 is used, and the typical user, I don't think there's going to be a tremendous difference in blocking malware sites. They use very similar databases."

In fact, Firefox, Chrome and Safari all turn to the same source for their blacklist: Google's SafeBrowsing API. Moy wasn't able to completely explain why, if that's the case, the three browsers' scores were so different in the NSS tests. He did, however, speculate that while each browser pings Google's blacklist, they handle the information differently, and may add or subtract from it using their own algorithms.

"The implementation [of SafeBrowsing] is different in Firefox than the others using it," Moy said.

The NSS report can be downloaded from the company's Web site (PDF download). NSS has also scheduled a webinar for March 31 at 10 a.m. Pacific time, during which it will outline its results. Users can register for the session on the NSS site.

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