CVE-2014-8967

Vulnerabilidad de uso después de liberación en Microsoft Internet Explorer permite a atacantes remotos ejecutar código arbitrario a través de un documento HTML manipulado en conjunto con una secuencia de tokens Cascading Style Sheets (CSS) que especifica el valor run-in para la propiedad de muestra, que conduce a una cuenta de la referencia CElement incorrecta.

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Internet Explorer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The vulnerability relates to how Internet Explorer uses reference counting to manage the lifetimes of the in-memory objects representing HTML elements (CElement objects). By applying a CSS style of display:run-in to a page and performing particular manipulations, an attacker can cause an object's reference count to fall to zero prematurely, causing the object to be freed. Internet Explorer will then continue using this object after it has been freed. An attacker can leverage this vulnerability to execute code under the context of the current process.