Research by NSS Labs indicates that in its testing, Microsoft (NASDAQ:MSFT) Internet Explorer and Google (NASDAQ:GOOGL) Chrome are the safest browsers.

NSS, which bills itself as "the world's leading information security research and advisory company," recenlty unveiled the results of its Browser Security Comparative Analysis: Socially Engineered Malware. Over the course of 28 days, from March 13 through April 9, the firm tested the five, most popular browsers against 754 samples of real-world malicious software. The browsers were Apple (NASDAQ:AAPL) Safari 5, Google Chrome 25/26, Microsoft Internet Explorer 10, Mozilla Firefox 19, and Opera 12.

The results revealed significant safety differences.

Blocking technologies used by browsers (higher is better).
Source: NSS-Browser Security Comparative Analysis

By using a combination of three different safety tools, Internet Explorer and Chrome topped the list. Altogether, IE blocked about 99.6% of  all incoming malware; Chrome blocked 83.16%. Falling a distant third was Apple's Safari. Opera offered essentially no protection with 1.87%. 

NSS says the web browser is both "the primary vector by which malware is introduced to computers" and "the first line of defense against malware infection."

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