Security experts discovered a new severe XSS flaw affects fully patched Internet Explorer and exposes users to risks of attacks and identity theft. The flaw could be exploited by hackers to steal user sensitive data (i.e. login credentials) and inject malicious content into browsing sessions. Microsoft has declared that its experts are already developing a fix for the vulnerability that is effective on IE 11 running on both Windows 7 and 8.1.1. The bug allows an attacker to bypass the same origin policy (SOP), which is a fundamental in the web application security model implemented to protect users browsing experience.”]
Source: http://securityaffairs.co/wordpress/33089/security/severe-xss-flaw-explorer.html