TippingPoint Zero Day Initiative

Microsoft Office Word sprmCMajority Record Parsing Remote Code Execution Vulnerability

ZDI-10-150: August 11th, 2010


CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 10122. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Office Word. User interaction is required to exploit this vulnerability in that the target must open a malicious document.

The specific flaw exists in the parsing of sprmCMajority records in a Word document. Due to the lack of parameter checking when processing sprmCMajority sprm groups it is possible to arbitrarily control the amount of data being written to a stack based buffer resulting in a stack overflow vulnerability which can overwrite critical exception structures. Successful exploitation can lead to remote code execution under the credentials of the currently logged in user.

Vendor Response

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

Disclosure Timeline

    2009-07-14 - Vulnerability reported to vendor
    2010-08-11 - Coordinated public release of advisory


This vulnerability was discovered by:
    L.W.Z of team509