The vulnerability could lead to malicious code execution attacks if a Firefox user is lured to a Web site rigged with exploits. It affects all versions of the open-source browser, including the newest Firefox 3.0.7.7. The vulnerability [mozilla.org], released alongside proof-of-concept code [securityfocus.com] on several security sites, could be malicious code executions if a user was lured to an exploit site with exploits. It affects Firefox users of all versions, including those of the latest version of the browser.
Source: https://threatpost.com/firefox-scrambles-patch-zero-day-flaw-032609/72476/