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Microsoft Internet Explorer vulnerable to remote code execution

Vulnerability Note VU#771788

Original Release Date: 2007-02-14 | Last Revised: 2007-03-13


A vulnerability in the way Microsoft Internet Explorer instantiates COM objects may lead to execution of arbitrary code.


Component Object Model, or COM objects, are used to enable interprocess communication and dynamic object creation within Microsoft Windows. Microsoft Internet Explorer contains a vulnerability that could be exploited when it attempts to load specially crafted web sites that instantiate specific COM objects contained in Msb1fren.dll, Htmlmm.ocx, or Blnmgrps.dll. According to Microsoft Security Bulletin MS07-016

When Internet Explorer tries to instantiate certain COM objects as ActiveX controls, the COM objects may corrupt the system state in such a way that an attacker could execute arbitrary code.

Note that this vulnerability does not affect Windows Internet Explorer 7 in Windows Vista.


A remote, unauthenticated attacker may be able to execute arbitrary code or cause a denial-of-service condition.


Microsoft has released an update to address this issue. See Microsoft Security Bulletin MS07-016 for more details.

Disable ActiveX

Disabling ActiveX controls in the Internet Zone (or any zone used by an attacker) appears to prevent exploitation of this vulnerability. Instructions for disabling ActiveX in the Internet Zone can be found in the document Securing Your Web Browser and the Malicious Web Scripts FAQ.

Note that disabling ActiveX controls in the Internet Zone will reduce the functionality of some web sites.

Vendor Information


Microsoft Corporation Affected

Updated:  February 14, 2007



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


Refer to Microsoft Security Bulletin MS07-016.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

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This vulnerability was reported in Microsoft Security Bulletin MS07-016. Microsoft credits H D Moore of BreakingPoint Systems for reporting this issue.

This document was written by Chris Taschner.

Other Information

CVE IDs: CVE-2007-0219
Severity Metric: 25.65
Date Public: 2007-02-13
Date First Published: 2007-02-14
Date Last Updated: 2007-03-13 19:23 UTC
Document Revision: 19

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