ZDI-07-038: Microsoft Internet Explorer Prototype Dereference Code
            Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-07-038.html
June 12, 2007

-- CVE ID:
CVE-2007-1751

-- Affected Vendor:
Microsoft

-- Affected Products:
Internet Explorer 6.x
Internet Explorer 7.x

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability since October 10, 2006 by Digital Vaccine protection
filter ID 4761. For further product information on the TippingPoint IPS:

    http://www.tippingpoint.com 

-- Vulnerability Details:
This vulnerability allows attackers to execute arbitrary code on
vulnerable installations of Microsoft Internet Explorer. User
interaction is required to exploit this vulnerability in that the
target must visit a malicious page.

The flaw is specifically exposed when a prototype variable points to a
table cell and then that table cell is removed. This results in an
invalid pointer dereference which can be leveraged to result in
arbitrary code execution.

-- Vendor Response:
Microsoft has issued an update to correct this vulnerability. More
details can be found at:

    http://www.microsoft.com/technet/security/bulletin/ms07-033.mspx

-- Disclosure Timeline:
2006.10.10 - Digital Vaccine released to TippingPoint customers
2007.02.15 - Vulnerability reported to vendor
2007.06.12 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by Sam Thomas.

-- About the Zero Day Initiative (ZDI):
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through the ZDI can find more information and sign-up at:

    http://www.zerodayinitiative.com

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