ZDI-06-026: Microsoft Internet Explorer Multiple CSS Imports Memory
                       Corruption Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-06-026.html
August  8, 2006

-- CVE ID:
CVE-2006-3451

-- Affected Vendor:
Microsoft

-- Affected Products:
Internet Explorer 6 All Versions
Internet Explorer 5 SP4

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability since August  8, 2006 by Digital Vaccine protection
filter ID 4606. 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 specific flaw exists due to improper garbage collection when
multiple "imports" are used on a "styleSheets" collection. Crafting a
long chain of CSS imports in an HTML document results in a memory
corruption eventually leading to 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/MS06-042.mspx

-- Disclosure Timeline:
2006.06.14 - Vulnerability reported to vendor
2006.08.08 - Digital Vaccine released to TippingPoint customers
2006.08.08 - Coordinated public release of advisory

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

-- About the Zero Day Initiative (ZDI):
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(ZDI) represents a best-of-breed model for rewarding security
researchers for responsibly disclosing discovered vulnerabilities.

Researchers interested in getting paid for their security research
through the ZDI can find more information and sign-up at:

    http://www.zerodayinitiative.com

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