MS00-095: RAS Registry Modification Allowed Without Administrative Rights (267861)



The information in this article applies to:

  • Microsoft Windows NT Server 4.0
  • Microsoft Windows NT Server 4.0 SP1
  • Microsoft Windows NT Server 4.0 SP2
  • Microsoft Windows NT Server 4.0 SP3
  • Microsoft Windows NT Server 4.0 SP4
  • Microsoft Windows NT Server 4.0 SP5
  • Microsoft Windows NT Server 4.0 SP6a
  • Microsoft Windows NT Server, Enterprise Edition 4.0
  • Microsoft Windows NT Server, Enterprise Edition 4.0 SP4
  • Microsoft Windows NT Server, Enterprise Edition 4.0 SP5
  • Microsoft Windows NT Server, Enterprise Edition 4.0 SP6a
  • Microsoft Windows NT Workstation 4.0
  • Microsoft Windows NT Workstation 4.0 SP1
  • Microsoft Windows NT Workstation 4.0 SP2
  • Microsoft Windows NT Workstation 4.0 SP3
  • Microsoft Windows NT Workstation 4.0 SP4
  • Microsoft Windows NT Workstation 4.0 SP5
  • Microsoft Windows NT Workstation 4.0 SP6a

This article was previously published under Q267861

SYMPTOMS

Microsoft has released a tool that corrects the permissions on several registry values in Microsoft Windows NT 4.0. The default permissions could allow a malicious user to gain additional privileges on an affected machine.

The "RAS Administration" key, HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\RAS, provides a way to install third-party RAS products that work with the Windows NT native RAS service. By changing one of the values in this key, it would be possible for a malicious user to specify code of her choice as a third-party management tool. The code would then run in the LocalSystem security context. Although it might be possible to make the needed registry changes remotely, the malicious user's code would need to reside on the affected computer itself. RAS is not installed on Windows NT 4.0 machines by default.

For additional information about other registry keys affected by this tool, click the article numbers below to view the articles in the Microsoft Knowledge Base:

265714 Windows NT 4.0 SNMP Registry Entries Are Readable

267864 MTS Package Administration Key Includes Information About Users

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

RESOLUTION

To resolve this problem, obtain the individual package referenced below or obtain the Windows NT 4.0 Security Rollup Package. For additional information on the SRP, click the article number below to view the article in the Microsoft Knowledge Base:

299444 Post-Windows NT 4.0 Service Pack 6a Security Rollup Package (SRP)

The following file is available for download from the Microsoft Download Center:
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. NOTE: Due to file dependencies, this patch requires Windows NT 4.0 Service Pack 5 or later.

The English version of this fix should have the following file attributes or later:
   Date        Time    Size     File name     Platform
   ---------------------------------------------------
   06/23/2000  08:28p   42,256  Regacl40.exe  Intel
   06/23/2000  08:28p  161,040  Tcpcfg.dll    Intel

   06/23/2000  08:27p   96,016  Regacl40.exe  Alpha
   06/23/2000  08:26p  242,960  Tcpcfg.dll    Alpha
				

STATUS

Microsoft has confirmed that this problem may cause a degree of security vulnerability in Windows NT 4.0.

Modification Type:MajorLast Reviewed:6/15/2004
Keywords:kbbug kbfix kbgraphxlinkcritical KbSECBulletin kbSecurity KbSECVulnerability KB267861