A new vulnerability has been discovered that affects Internet Explorer 6, 7, 8 and 9 on Windows XP, Vista, 7 and 7, Windows Server 2003 and 2008. It is still unpatched at the time of this blog post. Microsoft released a security advisory to address reports that attacks are being leveraged against this 0-day vulnerability. The vulnerability is a “use-after-free” and exploiting it starts with the creation of an array with a large number of DOM objects. The references are no longer properly resolved once the objects are rewritten, allowing for improper address dereference.”]
Source: https://blog.talosintelligence.com/2012/09/internet-explorer-use-after-free-0-day.html