From secnotif@MICROSOFT.COM Fri Jul 6 04:13:38 2001 From: Microsoft Product Security To: MICROSOFT_SECURITY@ANNOUNCE.MICROSOFT.COM Date: Thu, 5 Jul 2001 18:08:16 -0700 Subject: Microsoft Security Bulletin MS01-037 The following is a Security Bulletin from the Microsoft Product Security Notification Service. Please do not reply to this message, as it was sent from an unattended mailbox. ******************************** -----BEGIN PGP SIGNED MESSAGE----- - - - ---------------------------------------------------------------------- Title: Authentication Error in SMTP Service Could Allow Mail Relaying Date: 05 July, 2001 Software: Windows 2000 Impact: Mail Relaying Bulletin: MS01-037 Microsoft encourages customers to review the Security Bulletin at: http://www.microsoft.com/technet/security/bulletin/MS01-037.asp. - - - ---------------------------------------------------------------------- Issue: ====== An SMTP service installs by default as part of Windows 2000 server products, and can be selected for installation on Windows 2000 Professional. A vulnerability results because of a flaw in the authentication process used by the service. The vulnerability could allow an unauthorized user to successfully authenticate to the service using incorrect credentials. An attacker who exploited the vulnerability could gain user-level privileges on the SMTP service, thereby enabling the attacker to use the service but not to administer it. The most likely purpose in exploiting the vulnerability would be to perform mail relaying via the server. Mitigating Factors: ==================== - Exchange servers -- even when run on Windows 2000 -- are not affected by this vulnerability. - Best practices recommend disabling unneeded services. If the SMTP service has been disabled, the vulnerability could not be exploited. - The vulnerability only affects stand-alone machines, not domain members. - Proper firewalling could prevent Internet-based attacks by blocking port 25 on servers that do not specifically need to accept SMTP traffic. Patch Availability: =================== - A patch is available to fix this vulnerability. Please read the Security Bulletin http://www.microsoft.com/technet/security/bulletin/ms01-037.asp for information on obtaining this patch. Acknowledgment: =============== - Joao Gouveia (tharbad@kaotik.org) - - - --------------------------------------------------------------------- THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. -----BEGIN PGP SIGNATURE----- Version: PGP Personal Privacy 6.5.3 iQEVAwUBO0UPRY0ZSRQxA/UrAQFAfgf/fJNuLjRMLrZWmTzs2YR8yS164sq3VPCx ZsU92MoVGiYIMnO+BdiL0DrJmjLUyRQ1D702xZ0j9FUINjX31f3CM5hvF2AljI5P Dfx+9hiCZJnY+tbvtMJB0dmx0tv8sapwNqHttr7LeFfsihE7J3+OmNp5I9IbtllB fi+h7qk7yoE7F0ztaVdkY1xkAeaqkeMWSyJ+u9GRG/5kSXzARr3UGKQwrj2viczM /YqAzUYkD4bFjcIjFtfjew2XMv+E2zl8Yx0FWX6piuMYOgAaWArJ8X3u4iNoBCdB AfqC73Scidn7T5g62IY/+m1WrSqGBW6yYBrdJxTJ3h1MrY4Ujz2P5A== =flPm -----END PGP SIGNATURE----- ******************************************************************* You have received this e-mail bulletin as a result of your registration to the Microsoft Product Security Notification Service. You may unsubscribe from this e-mail notification service at any time by sending an e-mail to MICROSOFT_SECURITY-SIGNOFF-REQUEST@ANNOUNCE.MICROSOFT.COM The subject line and message body are not used in processing the request, and can be anything you like. To verify the digital signature on this bulletin, please download our PGP key at http://www.microsoft.com/technet/security/notify.asp. For more information on the Microsoft Security Notification Service please visit http://www.microsoft.com/technet/security/notify.asp. For security-related information about Microsoft products, please visit the Microsoft Security Advisor web site at http://www.microsoft.com/security.