ZDI-11-197: Microsoft Internet Explorer vgx.dll imagedata Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-197

June 14, 2011

-- CVE ID:
CVE-2011-1266

-- CVSS:
9, (AV:N/AC:L/Au:N/C:P/I:P/A:C)

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Internet Explorer 8

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 11254. 
For further product information on the TippingPoint IPS, visit:

    http://www.tippingpoint.com

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

The specific flaw exists within vgx.dll while parsing VML objects from
the DOM. Specifically, the faulty code exists while handling imagedata
parameters during page deconstruction. By dynamically assigning an
attribute to an imagedata object the process can be made to access freed
memory. Successful exploitation can lead to code execution under the
context of the application.

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

http://www.microsoft.com/technet/security/Bulletin/MS11-052.mspx

-- Disclosure Timeline:
2011-01-21 - Vulnerability reported to vendor
2011-06-14 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous

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