The boys at Microsoft are working overtime this week;  for the 2nd time this year, yesterday they issued another "Out of Cycle" critical patch to the operating system.  It covers the following:

A remote code execution vulnerability exists as an invalid pointer reference in the data binding function of Internet Explorer. When data binding is enabled (which is the default state), it is possible under certain conditions for an object to be released without updating the array length, leaving the potential to access the deleted object's memory space. This can cause Internet Explorer to exit unexpectedly, in a state that is exploitable.

If you haven't already done so, update your PC!