A remote code execution vulnerability exists in the way that Internet Explorer accesses an object that has been deleted or has not been properly allocated. The vulnerability may corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user within Internet Explorer. An attacker could host a specially crafted website that is designed to exploit this vulnerability through Internet Explorer and then convince a user to view the website.
Forget Microsoft's Advice For Avoiding A Critical Internet Explorer Security Bug--Just Use A Different Browser
On Monday, Microsoft issued a security advisory for Internet Explorer users running all versions from IE6 to IE9 running Windows 7 and earlier, warning of a security bug that can allow the takeover of the PC of any user tricked into visiting a website rigged to exploit the flaw. The hack, which was first spotted late last week by security researcher Eric Romang, is already being used to install the Poison Ivy trojan by some of the same cybercriminal operations that earlier exploited a security flaw in Java, and security firm Rapid7 estimates that the bug affects 41% of users in North America and 32% of users worldwide.