iDefense Security Advisory 12.14.10 http://labs.idefense.com/intelligence/vulnerabilities/ Dec 14, 2010 I. BACKGROUND Internet Explorer is a graphical web browser developed by Microsoft Corp. that has been included with Microsoft Windows since 1995. For more information about Internet Explorer, please the visit following website: http://www.microsoft.com/ie/ II. DESCRIPTION Remote exploitation of a memory corruption vulnerability in Microsoft Corp.'s Internet Explorer could allow an attacker to execute arbitrary code with the privileges of the current user.

T During the instantiation of multiple ActiveX Controls, a particular object is created along with multiple references that point to the object. The object can be destroyed and its associated references removed. However, a reference can incorrectly remain pointing to the object. The invalid object resides in uninitialized memory, which the attacker may control to gain arbitrary execution control. III. ANALYSIS Exploitation of this vulnerability results in the execution of arbitrary code with the privileges of the user viewing the web page. To exploit this vulnerability, a targeted user must load a malicious webpage created by an attacker. An attacker typically accomplishes this via social engineering or injecting content into a compromised, trusted site. IV. DETECTION Microsoft Internet Explorer 6, 7 and 8 are vulnerable. V. WORKAROUND Microsoft suggested workarounds can be found in Microsoft Security Bulletin MS10-090. VI. VENDOR RESPONSE Microsoft Corp. has released patches which address this issue. Information about downloadable vendor updates can be found by clicking on the URLs shown. http://www.microsoft.com/technet/security/Bulletin/MS10-090.mspx VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2010-3340 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org/), which standardizes names for security problems. VIII. DISCLOSURE TIMELINE 03/24/2010 Initial Vendor Notification 03/24/2010 Initial Vendor Reply 12/14/2010 Coordinated Public Disclosure IX. CREDIT This vulnerability was reported to iDefense by Aniway. Get paid for vulnerability research http://labs.idefense.com/methodology/vulnerability/vcp.php Free tools, research and upcoming events http://labs.idefense.com/ X. LEGAL NOTICES Copyright © 2010 iDefense, Inc. Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please e-mail customerservice@idefense.com for permission. Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.