CVE-2017-7784

Puede ocurrir una vulnerabilidad de uso de memoria previamente liberada al leer un observador de imagen durante la reconstrucción de frames una vez se ha liberado el observador. Esto resulta en un cierre inesperado potencialmente explotable. La vulnerabilidad afecta a Thunderbird en versiones anteriores a la 52.3, Firefox ESR en versiones anteriores a la 52.3 y Firefox en versiones anteriores a la 55.

USN-3391-1 fixed vulnerabilities in Firefox. The update introduced a performance regression with WebExtensions. This update fixes the problem. Multiple security issues were discovered in Firefox. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit these to conduct cross-site scripting attacks, bypass sandbox restrictions, obtain sensitive information, spoof the origin of modal alerts, bypass same origin restrictions, read uninitialized memory, cause a denial of service via program crash or hang, or execute arbitrary code. Various other issues were also addressed.