The vulnerability, which also affects the Thunderbird email product and SeaMonkey cross-platform internet suite, enables a remote attacker to cause a denial of service through an application crash or to execute arbitrary code.
Mozilla developers Andrew McCreight and Olli Pettay discovered that “ReadPrototypeBindings will leave a XBL binding in a hash table even when the function fails. If this occurs, when the cycle collector reads this hash table and attempts to do a virtual method on this binding a crash will occur. This crash may be potentially exploitable”, the company said in a security advisory.
Firefox 9 and earlier versions are not affected by the vulnerability, Mozilla explained.
In addition, Mozilla announced plans to create a Metro version of Firefox for Windows 8. The application will be based on the open source Gecko layout engine and will take advantage of the full screen touch enhancements of Microsoft's new Windows 8 Metro style apps, alongside support for the Awesomebar, tabs, and common navigation controls.