Public Vulnerability Reports

Microsoft Outlook mailto Command Line Switch Injection



Microsoft Outlook provides an integrated solution for managing and organizing e-mail messages, schedules, tasks, notes, contacts, and other information. More information is available at the following URL.


Remote exploitation of an input validation error in the handling of "mailto" URIs by Microsoft Corp.'s Outlook may allow arbitrary code execution.

It is possible to construct a "mailto" URI which causes the web browser to pass extra command line switches to Outlook. These switches can modify Outlook's account configuration.


Exploitation of this vulnerability may allow an attacker to access sensitive information or take complete control of an affected system. In order to exploit this vulnerability, an attacker would have to convince a user to view an attacker-controlled website.


iDefense has confirmed the existence of this vulnerability in Microsoft Outlook 2007 on Windows XP SP2. Previous versions may also be affected.


Disabling the "mailto" URI handler will prevent exploitation of this vulnerability. However, doing so will also disable e-mail links within all applications.


Microsoft has addressed this vulnerability with Security Bulletin MS08-015. For more information, consult their bulletin at the following URL.


The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2008-0110 to this issue. This is a candidate for inclusion in the CVE list (, which standardizes names for security problems.


07/03/2007 Initial vendor notification
07/03/2007 Initial vendor response
03/11/2008 Coordinated public disclosure


This vulnerability was discovered by Greg MacManus of iDefense Labs.

Get paid for vulnerability research

Free tools, research and upcoming events


Copyright © 2008 Verisign, Inc.

Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please e-mail customer service for permission.

Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.