Exchange Server 2003 Folder Listing DoS

A Secunia publicou recentemente um alerta relativamente a uma vulnerabilidade do Exchange Server 2003, que possibilita um ataque do tipo Denial of Service (DoS):

Description:
A vulnerability has been reported in Microsoft Exchange Server 2003, which can be exploited by malicious users to cause a DoS (Denial of Service).The vulnerability is caused due to an unspecified error in the handling of requests to list public folders, and can be exploited to crash the Microsoft Exchange Information Store service (Store.exe) via an IMAP4 request.Successful exploitation requires that the following conditions are met:
* User tries to list public folders using IMAP4 version 4rev1
* Exchange server does not allow IMAP4 users to list public folders.
* User does not have a private mailbox on the server.

Solution:
The vendor has issued a hotfix, which can be obtained by contacting Microsoft Product Support Services.