ZDI-07-073: Microsoft Internet Explorer setExpression Code Execution 
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-07-073.html
December 11, 2007

-- CVE ID:
CVE-2007-3902

-- Affected Vendor:
Microsoft

-- Affected Products:
Internet Explorer 5.01 SP4
Internet Explorer 6
Internet Explorer 7

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

    http://www.tippingpoint.com 

-- Vulnerability Details:
This vulnerability allows remote 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 specific flaw exists in the CRecalcProperty function in mshtml.dll.
When rendering HTML after calling the setExpression methods, followed by
a modification of the outerHTML property of a programatically created
element. The vulnerable code dereferences a previously freed memory
location which can be leveraged to execute arbitrary code.

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

http://www.microsoft.com/technet/security/bulletin/ms07-069.mspx

-- Disclosure Timeline:
2007.07.20 - Vulnerability reported to vendor
2007.12.11 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by an anonymous researcher.

-- About the Zero Day Initiative (ZDI):
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    http://www.zerodayinitiative.com

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