Public Vulnerability Reports

Microsoft Excel Invalid Column Heap Corruption Vulnerability



Microsoft Excel is the spreadsheet application from the Microsoft Office System. More information is available at the following link:


Remote exploitation of an input validation error in Microsoft Corp.'s Excel spreadsheet application may allow the execution of arbitrary code.

The vulnerability specifically exists in the handling of out of range values in the column field in several BIFF8 record types. By supplying an invalid Column field to one of these records, it is possible to cause the system to reference arbitrary memory. This can be exploited to gain control of the application.


Successful exploitation of this vulnerability would allow an attacker to execute arbitrary code in the context of the user who opened the document. In order exploit this vulnerability, an attacker would need to convince the target to open an Excel spreadsheet file. As memory offsets and other values differ slightly between versions, the attacker would need to know the version of Excel the targeted user had installed.


iDefense has confirmed the existence of this vulnerability in Microsoft Excel 2003 with all available service packs and security patches. Previous versions of Excel are also likely to be affected.


Do not follow links or open files from unknown sources or that you were not expecting to receive.


Microsoft has addressed this vulnerability with Microsoft Security Bulletin MS07-002. A link to this bulletin can be found below.


The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2007-0030 to this issue. This is a candidate for inclusion in the CVE list (, which standardizes names for security problems.


09/14/2006 Initial vendor notification
09/15/2006 Initial vendor response
01/09/2007 Coordinated public disclosure


This vulnerability was discovered by Greg MacManus, iDefense Labs.

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Copyright © 2006 Verisign, Inc.

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