CVE-2015-4498

Vulnerabilidad en la funcionalidad de instalación de complemento en Mozilla Firefox en versiones anteriores a 40.0.3 y Firefox ESR 38.x en versiones anteriores a 38.2.1, permite a atacantes remotos eludir un requisito destinado a la confirmación de usuario por la construcción de un dato manipulado: URL y desencadenando la navegación a una URL http: o https: arbitraria en un cierto punto temprano del proceso de instalación.

A flaw was found in the way Firefox handled installation of add-ons. An attacker could use this flaw to bypass the add-on installation prompt, and trick the user into installing an add-on from a malicious source.

A use-after-free was discovered when resizing a canvas element during restyling in some circumstances. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit this to cause a denial of service via application crash, or execute arbitrary code with the privileges of the user invoking Firefox. Bas Venis discovered that the addon install permission prompt could be bypassed using data: URLs in some circumstances. It was also discovered that the installation notification could be made to appear over another site. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit this to install a malicious addon. Various other issues were also addressed.