For many years, people "in the know" have propagated stories claiming Microsoft Internet Explorer is inferior to Firefox, Opera, Safari and Google Chrome when it comes to security vulnerabilities. Unbeknownst to these same people, security specialists NSS Labs have been testing the top 5 internet browsers and their findings make for surprising reading.

Over the past year, NSS Labs have been testing the latest versions of Internet Explorer, Mozilla Firefox, Apple's Safari, Opera and Google Chrome for their handling of "socially-engineered malware". In essence, socially engineered malware is "a web page link leading directly to a download that delivers a malicious payload". NSS Labs' test ran for 18 days monitoring how each of the browsers performed in detecting and blocking the malware from sites they had previously identified.

The results of the test show Microsoft Internet Explorer 8 blocking 85% of the malware encountered. The nearest rival browser had Mozilla Firefox and Apple Safari tied on a meagre 29% block rate. Google Chrome came in with a 17% blocking success rate and Opera polled last with less than 1% of the malware encountered being successfully blocked.

Such results show that Internet Explorer is more than twice as secure as Mozilla Firefox when it comes to blocking malware, turning many commonly held beliefs regarding browser safety on their heads. Moreover, historical tests show that Internet Explorer safety has increased consistently over the past year, where all of the other browsers tested varied wildly and Opera and Firefox actually decreased in effectiveness since the start of 2009.

Such results should give network administrators and those with security responsibilities at work pause for thought before migrating platforms based on misinformation and prejudice.

More detailed analysis of the NSS Labs tests can be found on their website.