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ZDI-11-287 : Internet Explorer Select Element Cache Remote Code
Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-11-287
October 15, 2011

- -- CVE ID:
CVE-2011-1996

- -- CVSS:
7.5, AV:N/AC:L/Au:N/C:P/I:P/A:P

- -- Affected Vendors:

Microsoft



- -- Affected Products:

Microsoft Internet Explorer



- -- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 11759.
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 Microsoft 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 the caching implementation of a Select
element. When modifying this cache, there are certain methods that do
not update the cache correctly. Due to these inconsistencies, one can
desynchronize the cache with elements that have been freed. While
using these freed elements, the application's perception of
type-safety becomes skewed and usage of the object 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://technet.microsoft.com/en-us/security/bulletin/ms11-081



- -- Disclosure Timeline:
2011-06-03 - Vulnerability reported to vendor
2011-10-15 - Coordinated public release of advisory

- -- Credit:
This vulnerability was discovered by:

* Ivan Fratric


*  http://ifsec.blogspot.com/



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