Mozilla Firefox is an open source Web browser. XULRunner provides the XUL Runtime environment for Mozilla Firefox. A flaw was found in the processing of malformed web content. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code as the user running Firefox. For technical details regarding this flaw, refer to the Mozilla security advisory for Firefox 3.0.10. You can find a link to the Mozilla advisories in the References section of this errata. All Firefox users should upgrade to these updated packages, which contain Firefox version 3.0.10, which corrects this issue. After installing the update, Firefox must be restarted for the change to take effect.