CVE-2015-0816

Mozilla Firefox anterior a 37.0, Firefox ESR 31.x anterior a 31.6, y Thunderbird anterior a 31.6 no restringe correctamente las URLs resource:, lo que facilita a atacantes remotos ejecutar código JavaScript arbitrario con privilegios chrome mediante el aprovechamiento de la habilidad de evadir Same Origin Policy, tal y como fue demostrado por la URL resource: asociada con PDF.js.

A flaw was found in the way documents were loaded via resource URLs in, for example, Mozilla's PDF.js PDF file viewer. An attacker could use this flaw to bypass certain restrictions and under certain conditions even execute arbitrary code with the privileges of the user running Firefox.

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Mozilla Firefox. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the handling of documents loaded through the resource: URL. As the same flag was used for chrome: and resource: URLs, these pages were able to subsequently load privileged chrome pages. By combining this with a same-origin policy bypass, an attacker could execute arbitrary code in the context of the current user.

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 documents were loaded via resource URLs in, for example, Mozilla's PDF.js PDF file viewer. An attacker could use this flaw to bypass certain restrictions and under certain conditions even execute arbitrary code with the privileges of the user running Firefox.