Microsoft has released a Security Update to address a vulnerability in Internet Explorer 7, 8 and 9 on Windows XP, Vista and 7

Microsoft is investigating public reports of a vulnerability in Internet Explorer 6, Internet Explorer 7, Internet Explorer 8, and Internet Explorer 9. Internet Explorer 10 is not affected. Microsoft is aware of targeted attacks that attempt to exploit this vulnerability. Applying the Microsoft Fix it solution, "Prevent Memory Corruption via ExecCommand in Internet Explorer," prevents the exploitation of this issue. See the Suggested Actions section of this advisory for more information.
A remote code execution vulnerability exists in the way that Internet Explorer accesses an object in memory 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.
On completion of this investigation, Microsoft will take the appropriate action to protect our customers, which may include providing a solution through our monthly security update release process, or an out-of-cycle security update, depending on customer needs.
We are actively working with partners in our Microsoft Active Protections Program (MAPP) to provide information that they can use to provide broader protections to customers. In addition, we are actively working with partners to monitor the threat landscape and take action against malicious sites that attempt to exploit this vulnerability.
Microsoft continues to encourage customers to follow the guidance in the Microsoft Safety & Security Center of enabling a firewall, applying all software updates and installing anti-virus and anti-spyware software.

Microsoft has released a Microsoft security advisory about this issue for IT professionals. The security advisory contains additional security-related information. To view the security advisory, go to the following Microsoft website:Microsoft Security Advisory (2757760): Vulnerability in Internet Explorer Could Allow Remote Code Execution

To have us fix this problem for you, go to the "Fix it for me" section.
The "Prevent Memory Corruption via ExecCommand in Internet Explorer" Fix it solution that is described in this section is not intended to be a replacement for any security update. We recommend that you always install the latest security updates. However, we offer this Fix it solution as a workaround option for some scenarios.

For more information about this workaround, go to the following Microsoft Security Advisory webpage:Microsoft Security Advisory (2757760): Vulnerability in Internet Explorer Could Allow Remote Code Execution
The advisory provides more information about the issue, including the following:
  • The scenarios in which you might apply or disable the workaround.
  • How to manually apply the workaround.

Specifically, to see this information, expand the Suggested actions section, and then expand the Workarounds section.

To enable or disable this Fix it solution, click the Fix it button or link under the Enable heading or under the Disableheading. Click Run in the File Download dialog box, and then follow the steps in the Fix it wizard.

Notes
  • For computers that are running 64-bit operating systems, the following Fix it solution only applies to 32-bit versions of Internet Explorer.
  • Before you apply this Fix it solution, you must ensure that Internet Explorer is fully updated by using the Windows Update service.

Microsoft Security Advisory: Vulnerability in Internet Explorer could allow remote code execution

Microsoft Security Advisory (2757760): Vulnerability in Internet Explorer Could Allow Remote Code Execution