According to a study by The Swiss Federal Institute of Technology, Google and IBM's Internet Security Services, Mozilla Firefox users are the safest Web surfers on the Internet.

Researchers determined Firefox users are by far the safest Web surfers on the Web during an 18-month study. The study based its conclusions of safety on how often users of different browsers updated to the most recent version of browser software. Much of the credit to Firefox's safety ranking stems from its ease of self updating by the software. Unlike IE which has to update via Windows Update, Firefox has a self-contained updating mechanism which translates into Mozilla users being far more likely to have the most up-to-date (and safest) version of their browser.

Firefox users were far and away the most likely to use the latest version, with an overwhelming 83.3 percent running an updated browser on any given day. However, despite Firefox's single click integrate auto-update functionality, 16.7 percent of Firefox users still continue to access the Web with an outdated version of the browser, researchers said. The study also revealed that the majority of Safari users (65.3) percent were likely to use the latest version of the browser between December 2007 and June 2008, after Safari version 3 became available. Meanwhile, Microsoft's Internet Explorer users ranked last in terms of safe browsing. Between January 2007 and June 2008, less than half of IE users — 47.6 percent — were running the most secure browser version during the same time period.

According to the study titled "Understanding the Web browser threat: Examination of vulnerable online Web browser populations and the 'insecurity iceberg,'" 83 percent of Firefox users had the most recent version. Next, Safari users (65 percent) were likely to use the latest version of the browser. The study concluded that only 48 percent of IE users were surfing the Internet with the most recent version of IE.

Microsoft is still at a loss to fix the problem, because unlike most malicious software the zero-day flaw allows code to be embedded into the user's operating system and shows no signs of any unusual activity, at least by current modes of malware detection.