Firefox accounted for 44 percent of all browser vulnerabilities in the first half of 2009. Apple s Safari had 35.percent of all reported browser vulnerability, Microsoft s Internet.com/Explorer was third at 15 percent and Opera had just six percent share. The 2009 figures stand in contrast to Cenzic’s Q3/Q4 2008 report, where IE accounted for 43 percent of. all reported Web browser vulnerabilities and. Firefox followed closely at 39 percent. Microsoft warns of the upcoming demise of the once dominant browser.
Source: https://threatpost.com/firefox-safari-top-browser-vulnerability-list-110909/73056/