MS01-037: Authentication error in SMTP service could allow mail relaying (302755)


The information in this article applies to:

  • Microsoft Windows 2000 Server SP1
  • Microsoft Windows 2000 Server SP2
  • Microsoft Windows 2000 Advanced Server SP1
  • Microsoft Windows 2000 Advanced Server SP2
  • Microsoft Windows 2000 Professional SP1
  • Microsoft Windows 2000 Professional SP2
This article was previously published under Q302755

SYMPTOMS

A vulnerability exists in the Windows 2000 SMTP service that could enable an unauthorized user to conduct mail relaying by using a Windows 2000 server. This could enable an attacker to disguise the origination point of an e-mail message, or co-opt a server's resources for mass mailings. The vulnerability is subject to the following constraints:
  • It would only affect servers that are running the native Windows 2000 Mail service. Mail servers that are running Microsoft Exchange (even on Windows 2000) would not be affected.
  • Even a computer that has the native Windows 2000 Mail service installed would only be affected if it were configured as a stand-alone computer rather than a member of a domain.
  • Proper use of a firewall could be used to prevent Internet users from exploiting the vulnerability.

CAUSE

This vulnerability results because of an authentication error in the SMTP service that installs as part of Microsoft Internet Information Services (IIS). In the case where the server is a stand-alone computer rather than a domain member, it could be possible for an unauthorized user to authenticate to the computer and use it for mail relaying.

RESOLUTION

To resolve this problem, either obtain the hotfix referenced in this section or Windows 2000 Security Rollup Package 1 (SRP1). For additional information about SRP1, click the following article number to view the article in the Microsoft Knowledge Base:

311401 Windows 2000 Security Rollup Package 1 (SR about SRP1), January 2002

To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

260910 How to obtain the latest Windows 2000 service pack

The following file is available for download from the Microsoft Download Center:
English (US):
DownloadDownload Q302755_w2k_sp3_x86_en.exe now

German:
DownloadDownload Q302755_w2k_sp3_x86_de.exe now

Release Date: July 5, 2001

For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to Obtain Microsoft Support Files from Online Services

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file.

The English version of this fix should have the following file attributes or later:
   Date        Time   Version          Size     File name
   --------------------------------------------------------
   6/25/2001   08:13p   5.0.2195.3712   320,784   Aqueue.dll
   6/25/2001   08:13p   5.0.2195.3712    66,832   Mailmsg.dll
   6/25/2001   08:13p   5.0.2195.3649    38,160   Ntfsdrv.dll
   6/25/2001   08:13p   5.0.2195.3779   434,448   Smtpsvc.dll

STATUS

Microsoft has confirmed that this problem may cause a degree of security vulnerability in Microsoft Windows 2000. This problem was first corrected in Windows 2000 Service Pack 3.

MORE INFORMATION

For more information about this vulnerability, please see the following Microsoft Web site:

http://www.microsoft.com/technet/security/bulletin/ms01-037.asp

For additional information about how to obtain a hotfix for Windows 2000 Datacenter Server, click the following article number to view the article in the Microsoft Knowledge Base:

265173 Datacenter Program and Windows 2000 Datacenter Server Product

For additional information about how to install multiple hotfixes with only one reboot, click the following article number to view the article in the Microsoft Knowledge Base:

296861 Use QChain.exe to install multiple hotfixes with one reboot

Modification Type:MajorLast Reviewed:10/8/2006
Keywords:kbHotfixServer kbQFE kbbug kbenv kbfix KbSECHack kbSecurity KbSECVulnerability kbSysAdmin kbWin2000PreSP3Fix kbWin2000sp3fix KB302755
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