Microsoft Internet Explorer is prone to a security-bypass vulnerability that affects the XSS Filter. An attacker can exploit this issue by tricking an unsuspecting victim into viewing a page containing malicious content. They can then execute arbitrary script code in the context of the user running the application. This may allow the attacker to steal cookie-based authentication credentials and other sensitive data that may aid in further attacks. Other attacks are possible. Internet Explorer 8, 9, 10, and 11 are vulnerable.
Run all non-administrative software as a non-administrative user with the least amount of privileges required to successfully operate. This will greatly reduce the potential damage that successful exploitation may achieve.
Never follow links provided by unknown or untrusted sources.
Since the exploitation of some of these issues allows the execution of malicious script code in web clients, consider disabling support for script code and active content within the client browser. Note that this mitigation tactic might adversely affect websites that rely on the execution of browser-based script code.
Updates are available. Please see the references or vendor advisory for more information.