Users should exercise caution at websites until Microsoft completes the full patch:

http://www.symantec.com/connect/blogs/new-internet-explorer-zero-day-found-targeted-attacks

http://technet.microsoft.com/en-us/security/advisory/2887505

QUOTE:  On September 17, Microsoft issued an advisory reporting a new zero-day vulnerability in Internet Explorer: Microsoft Internet Explorer Memory Corruption Vulnerability (CVE-2013-3893). The advisory states that the vulnerability may corrupt memory in a way that could allow attackers to execute arbitrary code. The attack works by enticing users to visit specially crafted websites that host the vulnerability through Internet Explorer. Microsoft also states that at this time the vulnerability is known to be exploited in only a limited number of targeted attacks.  While Microsoft is yet to release a patch for this vulnerability, they have provided a temporary “Fix It” tool solution as a workaround until a security update is made available