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ZDI-11-288 : Microsoft Internet Explorer Select Element Insufficient
Type Checking Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-11-288
October 15, 2011

- -- CVE ID:
CVE-2011-1999

- -- 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 11725.
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 8. 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 how the application verifies arguments
for a certain operation performed on an element. When parsing one of the
operands of a method, the application will pass the argument straight to
a method that will use the variant as an index. Due to bypassing the
argument check, an aggressor can set the index to point to data outside
the bounds of the array. This 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:
2011-06-29 - 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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