ZDI-11-043: Microsoft Excel 2007 Office Drawing Layer Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-043

February 7, 2011 - This vulnerability is being disclosed publicly without a patch in accordance with the ZDI 180 day deadline. To view mitigations for this vulnerability please see: http://dvlabs.tippingpoint.com/blog/2011/02/07/zdi-disclosure-microsoft

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

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Office Word

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10818. 
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 Excel 2007. 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 application's support for the office
drawing file format. When parsing shape data within a particular
container, the application will add a reference to an object to a linked
list. If an error occurs during parsing, the application will free each
element yet fail to remove the reference. Afterward, the application
will use this reference. This can lead to code execution under the
context of the application.

-- Disclosure Timeline:
2010-06-30 - Vulnerability reported to vendor
2011-02-07 - Public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous
    * Aniway (Aniway.Anyway AT gmail DOT com)

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