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  3. Microsoft Windows Telnet NTLM Credential Reflection Authentication Bypass Vulnerability

Microsoft Windows Telnet NTLM Credential Reflection Authentication Bypass Vulnerability

Risk

High

Date Discovered

August 11, 2009

Description

Microsoft Windows is prone to an authentication-bypass vulnerability in the Telnet protocol. An attacker can exploit this issue to gain unauthorized access to the affected computer with the privileges of the victim. Successful exploits may compromise the affected computer.

Technologies Affected

  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Advanced Server SP1
  • Microsoft Windows 2000 Advanced Server SP2
  • Microsoft Windows 2000 Advanced Server SP3
  • Microsoft Windows 2000 Advanced Server SP4
  • Microsoft Windows 2000 Datacenter Server
  • Microsoft Windows 2000 Datacenter Server SP1
  • Microsoft Windows 2000 Datacenter Server SP2
  • Microsoft Windows 2000 Datacenter Server SP3
  • Microsoft Windows 2000 Datacenter Server SP4
  • Microsoft Windows 2000 Professional
  • Microsoft Windows 2000 Professional SP1
  • Microsoft Windows 2000 Professional SP2
  • Microsoft Windows 2000 Professional SP3
  • Microsoft Windows 2000 Professional SP4
  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Server SP1
  • Microsoft Windows 2000 Server SP2
  • Microsoft Windows 2000 Server SP3
  • Microsoft Windows 2000 Server SP4
  • Microsoft Windows Server 2003 Datacenter Edition Itanium SP1 Beta 1
  • Microsoft Windows Server 2003 Datacenter Edition SP1
  • Microsoft Windows Server 2003 Datacenter x64 Edition
  • Microsoft Windows Server 2003 Datacenter x64 Edition SP2
  • Microsoft Windows Server 2003 Enterprise Edition
  • Microsoft Windows Server 2003 Enterprise Edition Itanium
  • Microsoft Windows Server 2003 Enterprise Edition Itanium SP1
  • Microsoft Windows Server 2003 Enterprise Edition SP1
  • Microsoft Windows Server 2003 Enterprise x64 Edition
  • Microsoft Windows Server 2003 Enterprise x64 Edition SP2
  • Microsoft Windows Server 2003 Itanium
  • Microsoft Windows Server 2003 Itanium SP1
  • Microsoft Windows Server 2003 Itanium SP2
  • Microsoft Windows Server 2003 SP1
  • Microsoft Windows Server 2003 SP2
  • Microsoft Windows Server 2003 Standard Edition
  • Microsoft Windows Server 2003 Standard Edition SP1
  • Microsoft Windows Server 2003 Standard Edition SP2
  • Microsoft Windows Server 2003 Standard x64 Edition
  • Microsoft Windows Server 2003 Web Edition
  • Microsoft Windows Server 2003 Web Edition SP1
  • Microsoft Windows Server 2003 Web Edition SP2
  • Microsoft Windows Server 2003 x64 SP1
  • Microsoft Windows Server 2003 x64 SP2
  • Microsoft Windows Server 2008 Datacenter Edition
  • Microsoft Windows Server 2008 Datacenter Edition SP2
  • Microsoft Windows Server 2008 Enterprise Edition
  • Microsoft Windows Server 2008 Enterprise Edition SP2
  • Microsoft Windows Server 2008 Standard Edition
  • Microsoft Windows Server 2008 Standard Edition SP2
  • Microsoft Windows Server 2008 for 32-bit Systems
  • Microsoft Windows Server 2008 for 32-bit Systems SP2
  • Microsoft Windows Server 2008 for Itanium-based Systems
  • Microsoft Windows Server 2008 for Itanium-based Systems SP2
  • Microsoft Windows Server 2008 for x64-based Systems
  • Microsoft Windows Server 2008 for x64-based Systems SP2
  • Microsoft Windows Vista
  • Microsoft Windows Vista Business
  • Microsoft Windows Vista Business 64-bit edition
  • Microsoft Windows Vista Business 64-bit edition SP1
  • Microsoft Windows Vista Business 64-bit edition SP2
  • Microsoft Windows Vista Business SP1
  • Microsoft Windows Vista Business SP2
  • Microsoft Windows Vista Enterprise 64-bit edition
  • Microsoft Windows Vista Enterprise 64-bit edition SP1
  • Microsoft Windows Vista Enterprise 64-bit edition SP2
  • Microsoft Windows Vista Enterprise SP1
  • Microsoft Windows Vista Enterprise SP2
  • Microsoft Windows Vista Home Basic
  • Microsoft Windows Vista Home Basic 64-bit edition SP1
  • Microsoft Windows Vista Home Basic 64-bit edition SP2
  • Microsoft Windows Vista Home Basic SP1
  • Microsoft Windows Vista Home Basic SP2
  • Microsoft Windows Vista Home Premium
  • Microsoft Windows Vista Home Premium 64-bit edition
  • Microsoft Windows Vista Home Premium 64-bit edition SP1
  • Microsoft Windows Vista Home Premium 64-bit edition SP2
  • Microsoft Windows Vista Home Premium SP1
  • Microsoft Windows Vista Home Premium SP2
  • Microsoft Windows Vista SP1
  • Microsoft Windows Vista SP2
  • Microsoft Windows Vista Ultimate
  • Microsoft Windows Vista Ultimate 64-bit edition
  • Microsoft Windows Vista Ultimate 64-bit edition SP1
  • Microsoft Windows Vista Ultimate 64-bit edition SP2
  • Microsoft Windows Vista Ultimate SP1
  • Microsoft Windows Vista Ultimate SP2
  • Microsoft Windows Vista x64 Edition
  • Microsoft Windows Vista x64 Edition SP1
  • Microsoft Windows Vista x64 Edition SP2
  • Microsoft Windows XP
  • Microsoft Windows XP 64-bit Edition
  • Microsoft Windows XP 64-bit Edition SP1
  • Microsoft Windows XP Gold
  • Microsoft Windows XP Home
  • Microsoft Windows XP Home SP1
  • Microsoft Windows XP Home SP2
  • Microsoft Windows XP Home SP3
  • Microsoft Windows XP Media Center Edition
  • Microsoft Windows XP Media Center Edition SP1
  • Microsoft Windows XP Media Center Edition SP2
  • Microsoft Windows XP Media Center Edition SP3
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Professional SP1
  • Microsoft Windows XP Professional SP2
  • Microsoft Windows XP Professional SP3
  • Microsoft Windows XP Professional x64 Edition
  • Microsoft Windows XP Professional x64 Edition SP2
  • Microsoft Windows XP Professional x64 Edition SP3
  • Microsoft Windows XP Tablet PC Edition
  • Microsoft Windows XP Tablet PC Edition SP1
  • Microsoft Windows XP Tablet PC Edition SP2
  • Microsoft Windows XP Tablet PC Edition SP3

Recommendations

Block external access at the network boundary, unless external parties require service.

If global access isn't required, filter access to the affected computer at the network boundary. Restricting access to only trusted computers and networks might greatly reduce the likelihood of remote exploits.

Run all software as a nonprivileged user with minimal access rights.

To reduce the impact of latent vulnerabilities, run all applications with the minimal amount of privileges required for functionality.

Do not follow links provided by unknown or untrusted sources.

Do not follow links provided by untrusted users.

Do not use client software to access unknown or untrusted hosts from critical systems.

Users should be cautious when connecting to suspicious Telnet server shares.
The vendor has released an update. Please see the references for more information.

Credits

DilDog of @stake and Beau Butler
Copyright © Symantec Corporation.
Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Security Response. Reprinting the whole or part of this alert in any medium other than electronically requires permission from secure@symantec.com.

Disclaimer
The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.
Symantec, Symantec products, Symantec Security Response, and secure@symantec.com are registered trademarks of Symantec Corp. and/or affiliated companies in the United States and other countries. All other registered and unregistered trademarks represented in this document are the sole property of their respective companies/owners.

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