Reported July 9, 2003, by Microsoft.




  • Microsoft Windows 98

  • Microsoft Windows 98 Second Edition

  • Microsoft Windows Me

  • Microsoft Windows NT 4.0 Server

  • Microsoft Windows NT 4.0 Terminal Server Edition

  • Microsoft Windows 2000

  • Microsoft Windows XP

  • Microsoft Windows Server 2003




A new vulnerability exists in the HTML converter of Microsoft operating systems that can result in the execution of arbitrary code on the vulnerable computer. This vulnerability stems from a flaw in the way the HTML converter for Microsoft Windows handles a conversion request during a cut-and-paste operation. A specially crafted request to the HTML converter could cause the converter to fail in such a way that it could execute code in the context of the currently logged-in user. Because this functionality is used by Internet Explorer, a potential attacker could craft a specially formed Web page or HTML e-mail that would cause the HTML converter to run arbitrary code on a user's system. A user visiting an attacker’s Web site could allow the attacker to exploit the vulnerability without any other user action.





Microsoft has released Security Bulletin MS03-023, "Buffer Overrun In HTML Converter Could Allow Code Execution (823559)" to address this vulnerability and recommends that affected users immediately apply the patch mentioned in the bulletin.



Discovered by Microsoft.