TippingPoint Zero Day Initiative

Microsoft Internet Explorer Select Element Insufficient Type Checking Remote Code Execution Vulnerability

ZDI-11-288: October 15th, 2011


CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 11725. For further product information on the TippingPoint IPS:

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:

Disclosure Timeline

    2011-06-29 - Vulnerability reported to vendor
    2011-10-15 - Coordinated public release of advisory


This vulnerability was discovered by:
    Ivan Fratric