Mozilla Firefox is an open source web browser. XULRunner provides the XUL Runtime environment for Mozilla Firefox. Several flaws were found in the processing of malformed web content. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code with the privileges of the user running Firefox. A flaw was found in the way Same Origin Wrappers were implemented in Firefox. A malicious site could use this flaw to bypass the same-origin policy and execute arbitrary code with the privileges of the user running Firefox. A flaw was found in the embedded WebGL library in Firefox. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code with the privileges of the user running Firefox. Note: This issue only affected systems using the Intel Mesa graphics drivers. An out-of-bounds write flaw was found in the embedded Cairo library in Firefox. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code with the privileges of the user running Firefox. A flaw was found in the way Firefox handled the JavaScript history functions. A malicious site could cause a web page to be displayed that has a baseURI pointing to a different site, allowing cross-site scripting and phishing attacks. Red Hat would like to thank the Mozilla project for reporting these issues. Upstream acknowledges Olli Pettay, Jesse Ruderman, Boris Zbarsky, Christian Holler, Milan Sreckovic, Joe Drew, Cody Crews, miaubiz, Abhishek Arya, and Mariusz Mlynski as the original reporters of these issues. For technical details regarding these flaws, refer to the Mozilla security advisories for Firefox 17.0.5 ESR. You can find a link to the Mozilla advisories in the References section of this erratum. All Firefox users should upgrade to these updated packages, which contain Firefox version 17.0.5 ESR, which corrects these issues. After installing the update, Firefox must be restarted for the changes to take effect.