ZDI-11-120: Microsoft Office Excel RealTimeData Record Parsing Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-120

April 12, 2011

-- CVE ID:
CVE-2011-0101

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

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Office Excel 2002

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10872. 
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 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 flaw exists within the methods used for RealTimeData Record Parsing.
When handling a stTopic field has a bit set specifying double byte
characters in the following field the value of a global pointer is
improperly calculated. This pointer is later used in a memcpy operation
whose source is user supplied data. A remote attacker can exploit this
vulnerability to execute arbitrary code under the context of the user.

-- Vendor Response:
Microsoft has issued an update to correct this vulnerability. More
details can be found at:

http://www.microsoft.com/technet/security/bulletin/ms11-021.mspx

-- Disclosure Timeline:
2010-11-15 - Vulnerability reported to vendor
2011-04-12 - Coordinated public release of advisory

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

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