ZDI-11-193: Microsoft Internet Explorer DOM Modification Race Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-193

June 14, 2011

-- CVE ID:
CVE-2011-1256

-- 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 11269. 
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 how the application handles multiple
javascript modifications to the document. In certain instances the
application will free an object due to a modification and then later
access it again when attempting to destroy it. This re-use 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/MS11-050.mspx

-- Disclosure Timeline:
2011-02-28 - Vulnerability reported to vendor
2011-06-14 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Damian Put

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