ZDI-11-041: Microsoft Office Excel Office Art Object Parsing Remote Code Execution Vulnerability

[ZDI Disclosures <zdi-disclosures@xxxxxxxxxxxxxxxx>]

ZDI-11-041: Microsoft Office Excel Office Art Object Parsing Remote Code 
Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-041

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:
9, (AV:N/AC:L/Au:N/C:P/I:P/A:C)

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Office Excel

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Microsoft Office Excel. 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 way the application parses an Office
Art record within a Microsoft Excel Document. Specifically, when parsing
an office art object record, if an error occurs, the application will
add a stray reference to an element which is part of a linked list. When
receiving a window message, the application will proceed to navigate
this linked list. This will access a method from the malformed object
which 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

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