[SECURITY-L] CAIS-Alerta: Vulnerabilidade no subsistema POSIX do Windows (841872)

CSIRT - UNICAMP security em unicamp.br
Qua Jul 14 10:41:24 -03 2004


----- Forwarded message from Centro de Atendimento a Incidentes de Seguranca <cais em cais.rnp.br> -----

From: Centro de Atendimento a Incidentes de Seguranca <cais em cais.rnp.br>
Subject:  CAIS-Alerta: Vulnerabilidade no subsistema POSIX do Windows (841872)
To: rnp-alerta em cais.rnp.br, rnp-seg em cais.rnp.br
Date: Tue, 13 Jul 2004 19:08:42 -0300 (BRST)

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Prezados,

O CAIS esta' repassando o alerta divulgado pela Microsoft, intitulado 
"Microsoft Security Bulletin MS04-020: Vulnerability in POSIX Could Allow 
Code Execution (841872)", que trata de uma vulnerabilidade presente no 
subsistema POSIX do Windows, que pode ser explorada localmente permitindo 
a execucao de codigo arbritario.

O POSIX (Portable Operating System Interface for UNIX) é um subsistema do 
Windows que permite a execucao de programas que nao foram desenvolvidos 
originalmente para Windows. Uma vulnerabilidade neste subsistema permite a 
um usuario local a execucao de codigo malicioso com privilegios 
administrativos. Reparem que nao e' possivel explorar remotamente essa 
vulnerabilidade, e o atacante tera que possuir um logon valido no sistema.


Sistemas afetados:

. Microsoft Windows NT Workstation 4.0 Service Pack 6a
. Microsoft Windows NT Server 4.0 Service Pack 6a
. Microsoft Windows NT Server 4.0 Terminal Server Edition Service Pack 6
. Microsoft Windows 2000 Service Pack 2
. Microsoft Windows 2000 Service Pack 3
. Microsoft Windows 2000 Service Pack 4


Sistemas *nao* afetados:

. Microsoft Windows XP
. Microsoft Windows XP Service Pack 1
. Microsoft Windows XP 64-Bit Edition Service Pack 1
. Microsoft Windows XP 64-Bit Edition Version 2003
. Microsoft Windows Server 2003
. Microsoft Windows Server 2003 64-Bit Edition
. Microsoft Windows 98
. Microsoft Windows 98 Second Edition (SE)
. Microsoft Windows Millennium Edition (Me)


Correcoes disponiveis:

A correcao consiste na aplicacao dos correspondentes patches recomendados
pela Microsoft e disponiveis em:

. Microsoft Windows NT Workstation 4.0 Service Pack 6a
  http://www.microsoft.com/downloads/details.aspx?FamilyId=25993F70-191B-4E35-AA1B-0AA1A7027880&displaylang=en

. Microsoft Windows NT Server 4.0 Service Pack 6a
  http://www.microsoft.com/downloads/details.aspx?FamilyId=C2018A81-446C-4930-A6CC-EA5B5960FF05&displaylang=en

. Microsoft Windows NT Server 4.0 Terminal Server Edition Service Pack 6
  http://www.microsoft.com/downloads/details.aspx?FamilyId=9CFC4AF3-B0BC-4798-BC23-F45739E3B802&displaylang=en

. Microsoft Windows 2000 Service Pack 2
  http://www.microsoft.com/downloads/details.aspx?FamilyId=05203A7E-4A11-4F88-AA73-75A6C81466B8&displaylang=en

. Microsoft Windows 2000 Service Pack 3
  http://www.microsoft.com/downloads/details.aspx?FamilyId=05203A7E-4A11-4F88-AA73-75A6C81466B8&displaylang=en

. Microsoft Windows 2000 Service Pack 4
  http://www.microsoft.com/downloads/details.aspx?FamilyId=05203A7E-4A11-4F88-AA73-75A6C81466B8&displaylang=en


Mais informacoes:

. Microsoft Security Bulletin MS04-020
  Vulnerability in POSIX Could Allow Code Execution (841872)
  http://www.microsoft.com/technet/security/bulletin/ms04-020.mspx

. Microsoft Brasil Security
  http://www.microsoft.com/brasil/security

. Technet Brasil - Central de Seguranca
  http://www.technetbrasil.com.br/seguranca


Identificador do CVE (http://cve.mitre.org): CAN-2004-0210


O CAIS recomenda aos administradores de plataformas Microsoft que
mantenham seus sistemas e aplicativos sempre atualizados.


Os alertas do CAIS tambem sao oferecidos no formato RSS/RDF:

http://www.rnp.br/cais/alertas/rss.xml


Atenciosamente,

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Microsoft Security Bulletin MS04-020
Vulnerability in POSIX Could Allow Code Execution (841872)

Issued: July 13, 2004
Version: 1.0
Summary

Who should read this document: Customers who use Microsoft Windows 2000 
or Windows NT 4.0

Impact of Vulnerability: Local Elevation of Privilege

Maximum Severity Rating: Important

Recommendation: Customers should install the update at the earliest 
opportunity.

Security Update Replacement: None

Caveats: None

Tested Software and Security Update Download Locations:

Affected Software:


Microsoft Windows NT® Workstation 4.0 Service Pack 6a ~V Download the 
update


Microsoft Windows NT Server 4.0 Service Pack 6a ~V Download the update


Microsoft Windows NT Server 4.0 Terminal Server Edition Service Pack 6 ~V 
Download the update


Microsoft Windows 2000 Service Pack 2, Microsoft Windows 2000 Service Pack 
3, Microsoft Windows 2000 Service Pack 4 ~V Download the update

Non-Affected Software:


Microsoft Windows XP and Microsoft Windows XP Service Pack 1


Microsoft Windows XP 64-Bit Edition Service Pack 1


Microsoft Windows XP 64-Bit Edition Version 2003


Microsoft Windows Server~Y 2003


Microsoft Windows Server 2003 64-Bit Edition


Microsoft Windows 98, Microsoft Windows 98 Second Edition (SE), and 
Microsoft Windows Millennium Edition (Me)

The software in this list has been tested to determine if the versions are 
affected. Other versions either no longer include security update support 
or may not be affected. To determine the support lifecycle for your 
product and version, visit the following Microsoft Support Lifecycle Web 
site.
Top of section
General Information

Executive Summary

Executive Summary:

This update resolves a newly-discovered, privately reported vulnerability. 
A privilege elevation vulnerability exists in the POSIX operating system 
component (subsystem). The vulnerability is documented in the 
Vulnerability Details section of this bulletin.

An attacker who successfully exploited this vulnerability could take 
complete control of an affected system, including installing programs; 
viewing, changing, or deleting data; or creating new accounts that have 
full privileges.

We recommend that customers install the update at the earliest 
opportunity.

Severity Ratings and Vulnerability Identifiers:
Vulnerability Identifiers	Impact of Vulnerability	Windows NT 4.0 
Windows 2000

POSIX Vulnerability - CAN-2004-0210


Privilege Elevation


Important


Important

This assessment is based on the types of systems that are affected by the 
vulnerability, their typical deployment patterns, and the effect that 
exploiting the vulnerability would have on them.
Top of section

Frequently asked questions (FAQ) related to this security update

I'm still using Microsoft Windows NT 4.0 Workstation Service Pack 6a or 
Windows 2000 Service Pack 2, but extended security update support ended on 
June 30, 2004. However, this bulletin has a security update for these 
operating system versions. Why is that?
Windows NT 4.0 Workstation Service Pack 6a and Windows 2000 Service Pack 2 
have reached the end of their life cycles as previously documented, and 
Microsoft extended this support to June 30, 2004. However, the end-of-life 
for the extended support period occurred very recently. In this case, the 
majority of the steps that are required to address this vulnerability were 
completed before June 30, 2004. Therefore, we have decided to release 
security updates for these operating system versions as part of this 
security bulletin. We do not anticipate doing this for future 
vulnerabilities affecting these operating system versions, but we reserve 
the right to produce updates and to make these updates available when 
necessary.

It should be a priority for customers who have these operating system 
versions to migrate to supported versions to prevent potential exposure to 
future vulnerabilities. For more information about the Windows Product 
Life Cycle, visit the following Microsoft Support Lifecycle Web site. For 
more information about the extended security update support period for 
these operating system versions, visit the following Microsoft Product 
Support Services Web site.

Customers who require additional support for Windows NT Workstation 4.0 
SP6a must contact their Microsoft account team representative, their 
Technical Account Manager, or the appropriate Microsoft partner 
representative for custom support options. Customers without an Alliance, 
Premier, or Authorized Contract can contact their local Microsoft sales 
office. For contact information, visit the Microsoft Worldwide Information 
Web site, select the country, and then click Go to see a list of phone 
numbers. When you call, ask to speak with the local Premier Support sales 
manager.

For more information, see the Windows Operating System FAQ.

Can I use the Microsoft Baseline Security Analyzer (MBSA) to determine if 
this update is required?
Yes. MBSA will determine if this update is required. For more information 
about MBSA, visit the MBSA Web site.

Note After April 20, 2004, the Mssecure.xml file that is used by MBSA 
1.1.1 and earlier versions is no longer being updated with new security 
bulletin data. Therefore, scans that are performed after that date with 
MBSA 1.1.1 or earlier will be incomplete. All users should upgrade to MBSA 
1.2 because it provides more accurate security update detection and 
supports additional products. Users can download MBSA 1.2 from the MBSA 
Web site. For more information about MBSA support, visit the following 
Microsoft Baseline Security Analyzer 1.2 Q&A Web site.

Can I use Systems Management Server (SMS) to determine if this update is 
required?
Yes. SMS can help detect and deploy this security update. For information 
about SMS, visit the SMS Web site.

Top of section

Vulnerability Details

POSIX Vulnerability - CAN-2004-0210

A privilege elevation vulnerability exists in the POSIX subsystem. This 
vulnerability could allow a logged on user to take complete control of the 
system.

Mitigating Factors for POSIX Vulnerability - CAN-2004-0210:
~U

An attacker must have valid logon credentials and be able to logon locally 
to exploit this vulnerability. The vulnerability could not be exploited 
remotely or by anonymous users.
~U

Windows XP and Windows Server 2003 are not affected by this vulnerability.
Top of section

Workarounds for POSIX Vulnerability - CAN-2004-0210:

Microsoft has tested the following workarounds. While these workarounds 
will not correct the underlying vulnerability, they help block known 
attack vectors. When a workaround reduces functionality, it is identified 
below.


Disable the POSIX subsystem through the registry

This workaround is fully documented in Microsoft Knowledge Base Article 
101270. This article is summarized in the following paragraphs.

The following steps demonstrate how to disable the POSIX subsystem.

Note Using Registry Editor incorrectly can cause serious problems that may 
require you to reinstall your operating system. Microsoft cannot guarantee 
that problems resulting from the incorrect use of Registry Editor can be 
solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys 
And Values" Help topic in Registry Editor (Regedit.exe) or view the "Add 
and Delete Information in the Registry" and "Edit Registry Data" Help 
topics in Regedt32.exe.

Note We recommend backing up the registry before you edit it.

1.


Click Start, click Run, type "regedt32" (without the quotation marks), and 
then click OK.

2.


In Registry Editor, locate the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session 
Manager\Subsystems\Posix

3.


Click the POSIX data value, click Edit, and then click Delete.

4.


Click OK to confirm the delete, and then restart the system.

Note To enable the POSIX subsystem, re-create the registry key. The name 
if the registry key is Posix, the type of registry key is REG_EXPAND_SZ, 
and the registry key value is %SystemRoot%\system32\psxss.exe. After you 
have done this, restart the system.

Impact of Workaround: POSIX programs are disabled until the POSIX 
subsystem is enabled.
Top of section

FAQ for POSIX Vulnerability - CAN-2004-0210:

What is the scope of the vulnerability?
This is a privilege elevation vulnerability. An attacker who successfully 
exploited this vulnerability could take complete control of an affected 
system, including installing programs; viewing, changing, or deleting 
data; or creating new accounts that have full privileges.

What causes the vulnerability?
An unchecked buffer in the POSIX subsystem.

What is the POSIX subsystem?
You can run applications that are created for the Portable Operating 
System Interface for UNIX (POSIX) standard under Windows NT 4.0 and 
Windows 2000. The operating systems provide support for nonnative 
applications by emulating the environments in which they are designed to 
be processed. This support is provided through environment subsystems. 
Except for the Microsoft Win32 subsystem, which is the native environment 
of Windows, each environment is optional and is used only when a client 
application requires its services. For more information about POSIX 
support, visit the following MSDN Library Web Site.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could take 
complete control of the affected system.

Who could exploit the vulnerability?
To exploit the vulnerability, an attacker must be able to log on locally 
to a system that has the POSIX subsystem enabled.

How could an attacker exploit the vulnerability?
To exploit this vulnerability, an attacker would first have to log on to 
the system. An attacker could then run a specially-designed program that 
could attempt to exploit the vulnerability, and thereby gain complete 
control over the affected system.

An attacker could also access the affected component through another 
vector. For example, an attacker could use another program that passes 
parameters to the vulnerable component (locally or remotely).

What systems are primarily at risk from the vulnerability?
Windows NT 4.0 and Windows 2000 systems are at risk from this 
vulnerability. Windows XP and Windows Server 2003 do not contain the POSIX 
subsystem. For more information about the support of POSIX in Windows XP 
and in Windows Server 2003, see Microsoft Knowledge Base Article 308259.

Workstations and terminal servers are primarily at risk. Servers are only 
at risk if users who do not have sufficient administrative credentials are 
given the ability to log on to servers and to run programs. However, best 
practices strongly discourage allowing this.

Could the vulnerability be exploited over the Internet?
No. An attacker must be able to log on to the specific system that is 
targeted for attack. An attacker cannot load and run a program remotely by 
exploiting this vulnerability.

What does the update do?
The update removes the vulnerability by modifying the way that the POSIX 
subsystem validates the length of a message before it passes the message 
to the allocated buffer.

When this security bulletin was issued, had this vulnerability been 
publicly disclosed?
No. Microsoft received information about this vulnerability through 
responsible disclosure. Microsoft had not received any information 
indicating that this vulnerability had been publicly disclosed when this 
security bulletin was originally issued.

When this security bulletin was issued, had Microsoft received any reports 
that this vulnerability was being exploited?
No. Microsoft had not received any information indicating that this 
vulnerability had been publicly used to attack customers and had not seen 
any examples of proof of concept code published when this security 
bulletin was originally issued.
Top of section
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Security Update Information

Installation Platforms and Prerequisites:

For information about the specific security update for your platform, 
click the appropriate link:

Windows 2000 (all versions)

Prerequisites
For Windows 2000, this security update requires Service Pack 2 (SP2), 
Service Pack 3 (SP3), or Service Pack 4 (SP4).

The software that is listed has been tested to determine if the versions 
are affected. Other versions either no longer include security update 
support or may not be affected. To determine the support lifecycle for 
your product and version, visit the Microsoft Support Lifecycle Web site.

For more information about how to obtain the latest service pack, see 
Microsoft Knowledge Base Article 260910.

Inclusion in Future Service Packs:
The update for this issue will be included in Windows 2000 Service Pack 5.

Installation Information

This security update supports the following setup switches:

       /help                 Displays the command line options

Setup Modes

       /quiet                Quiet mode (no user interaction or display)

       /passive            Unattended mode (progress bar only)

       /uninstall          Uninstalls the package

Restart Options

       /norestart          Do not restart when installation is complete

       /forcerestart      Restart after installation

Special Options

       /l                        Lists installed Windows hotfixes or update 
packages

       /o                       Overwrite OEM files without prompting

       /n                       Do not backup files needed for uninstall

       /f                        Force other programs to close when the 
computer shuts down

       /extract             Extracts files without starting setup

Note You can combine these switches into one command. For backward 
compatibility, the security update also supports the setup switches that 
the previous version of the setup utility uses. For more information about 
the supported installation switches, see Microsoft Knowledge Base Article 
262841.

Deployment Information

To install the security update without any user intervention, use the 
following command at a command prompt for Windows 2000 Service Pack 2, 
Windows 2000 Service Pack 3, and Windows 2000 Service Pack 4:

Windows2000-kb841872-x86-enu /passive /quiet

To install the security update without forcing the system to restart, use 
the following command at a command prompt for Windows 2000 Service Pack 2, 
Windows 2000 Service Pack 3, and Windows 2000 Service Pack 4:

Windows2000-kb841872-x86-enu /norestart

For more information about how to deploy this security update with 
Software Update Services, visit the Software Update Services Web site.

Restart Requirement

In some cases, this update does not require a restart. The installer stops 
the required services, applies the update, and then restarts the services. 
However, if the required services cannot be stopped for any reason or if 
required files are in use, this update will require a restart. If this 
occurs, a message appears that advises you to restart.

Removal Information

To remove this security update, use the Add or Remove Programs tool in 
Control Panel.

System administrators can also use the Spuninst.exe utility to remove this 
security update. The Spuninst.exe utility is located in the 
%Windir%\$NTUninstallKB841872$\Spuninst folder. The Spuninst.exe utility 
supports the following setup switches:

/?: Show the list of installation switches.

/u: Use unattended mode.

/f: Force other programs to quit when the computer shuts down.

/z: Do not restart when the installation is complete.

/q: Use Quiet mode (no user interaction).

File Information

The English version of this update has the file attributes (or later) that 
are listed in the following table. The dates and times for these files are 
listed in coordinated universal time (UTC). When you view the file 
information, it is converted to local time. To find the difference between 
UTC and local time, use the Time Zone tab in the Date and Time tool in 
Control Panel.

Note Date, time, file name, or size information could change during 
installation. Refer to the Verifying Update Installation section for 
details on verifying an installation.

Windows 2000 Service Pack 2, Windows 2000 Service Pack 3, and Windows 2000 
Service Pack 4:

Date         Time   Version        Size     File name
- ------------------------------------------------------
16-May-2004  19:32  5.0.2195.6929  90,384   Psxss.exe

Verifying Update Installation


Microsoft Baseline Security Analyzer

To verify that a security update is installed on an affected system, you 
may be able to use the Microsoft Baseline Security Analyzer (MBSA) tool. 
This tool allows administrators to scan local and remote systems for 
missing security updates and for common security misconfigurations. For 
more information about MBSA, visit the Microsoft Baseline Security 
Analyzer Web site.


File Version Verification

Note Because there are several versions of Microsoft Windows, the 
following steps may be different on your computer. If they are, see your 
product documentation to complete these steps.

1.


Click Start, and then click Search.

2.


In the Search Results pane, click All files and folders under Search 
Companion.

3.


In the All or part of the file name box, type a file name from the 
appropriate file information table, and then click Search.

4.


In the list of files, right-click a file name from the appropriate file 
information table, and then click Properties.

Note Depending on the version of the operating system or programs 
installed, some of the files that are listed in the file information table 
may not be installed.

5.


On the Version tab, determine the version of the file that is installed on 
your computer by comparing it to the version that is documented in the 
appropriate file information table.

Note Attributes other than file version may change during installation. 
Comparing other file attributes to the information in the file information 
table is not a supported method of verifying the update installation. 
Also, in certain cases, files may be renamed during installation. If the 
file or version information is not present, use one of the other available 
methods to verify update installation.


Registry Key Verification

You may also be able to verify the files that this security update has 
installed by reviewing the following registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows 
2000\SP5\KB841872\Filelist

Note This registry key may not contain a complete list of installed files. 
Also, this registry key may not be created correctly when an administrator 
or an OEM integrates or slipstreams the 841872 security update into the 
Windows installation source files.
Top of section


Windows NT 4.0 (all versions)

Prerequisites
This security update requires Windows NT Workstation 4.0 Service Pack 6a 
(SP6a), Windows NT Server 4.0 Service Pack 6a (SP6a), or Windows NT Server 
4.0 Terminal Server Edition Service Pack 6 (SP6).

The software that is listed has been tested to determine if the versions 
are affected. Other versions either no longer include security update 
support or may not be affected. To determine the support lifecycle for 
your product and version, visit the following Microsoft Support Lifecycle 
Web site.

For more information about obtaining the latest service pack, see 
Microsoft Knowledge Base Article 152734.

Installation Information

This security update supports the following setup switches:

    /y: Perform removal (only with /m or /q )

    /f: Force programs to quit during the shutdown process

    /n: Do not create an Uninstall folder

    /z: Do not restart when the update completes

    /q: Use Quiet or Unattended mode with no user interface (this switch is 
a superset of /m )

    /m: Use Unattended mode with a user interface

    /l: List the installed hotfixes

    /x: Extract the files without running Setup

Note You can combine these switches into one command. For more information 
about the supported installation switches, see Microsoft Knowledge Base 
Article 262841.

Deployment Information

To install the security update without any user intervention, use the 
following command at a command prompt for Windows NT Server 4.0:

Windowsnt4server-kb841872-x86-enu /q

For Windows NT Server 4.0 Terminal Server Edition:

Windowsnt4terminalserver-kb841872-x86-enu /q

For Windows NT Workstation 4.0:

Windowsnt4workstation-kb841872-x86-enu /q

To install the security update without forcing the system to restart, use 
the following command at a command prompt for Windows NT Server 4.0:

Windowsnt4server-kb841872-x86-enu /z

For Windows NT Server 4.0 Terminal Server Edition:

Windowsnt4terminalserver-kb841872-x86-enu /z

For Windows NT Workstation 4.0:

Windowsnt4workstation-kb841872-x86-enu /z

For more information about how to deploy this security update with 
Software Update Services, visit the Software Update Services Web site.

Restart Requirement

In some cases, this update does not require a restart. The installer stops 
the needed services, applies the update, and then restarts the services. 
However, if the required services cannot be stopped for any reason or if 
required files are in use, this update will require a restart. If this 
occurs, a message appears that advises you to restart.

Removal Information

To remove this security update, use the Add/Remove Programs tool in 
Control Panel.

System administrators can also use the Hotfix.exe utility to remove this 
security update. The Hotfix.exe utility is located in the 
%Windir%\$NTUninstallKB841872$ folder. The Hotfix.exe utility supports the 
following setup switches:

/y: Perform removal (only with the /m or /q switch)

/f: Force programs to quit during the shutdown process

/n: Do not create an Uninstall folder

/z: Do not restart when the installation is complete

/q: Use Quiet or Unattended mode with no user interface (this switch is a 
superset of the /m switch)

/m: Use Unattended mode with a user interface

/l: List the installed hotfixes

File Information

The English version of this update has the file attributes (or later) that 
are listed in the following table. The dates and times for these files are 
listed in coordinated universal time (UTC). When you view the file 
information, it is converted to local time. To find the difference between 
UTC and local time, use the Time Zone tab in the Date and Time tool in 
Control Panel.

Note Date, time, filename, or size information could change during 
installation. Refer to the Verifying Update Installation section for 
details on verifying an installation.

Windows NT Workstation 4.0 and Windows NT Server 4.0:

Date         Time   Version        Size     File name
- ------------------------------------------------------
20-May-2004  15:04  4.0.1381.7269  93,968  Psxss.exe

Windows NT Server 4.0 Terminal Server Edition:

Date         Time   Version         Size     File name
- -------------------------------------------------------
21-May-2004  13:31  4.0.1381.33567  94,480   Psxss.exe

Verifying Update Installation


Microsoft Baseline Security Analyzer

To verify that a security update is installed on an affected system, you 
may be able to use the Microsoft Baseline Security Analyzer (MBSA) tool. 
This tool allows administrators to scan local and remote systems for 
missing security updates and for common security misconfigurations. For 
more information about MBSA, visit the Microsoft Baseline Security 
Analyzer Web site.


File Version Verification

Note Because there are several versions of Microsoft Windows, the 
following steps may be different on your computer. If they are, see your 
product documentation to complete these steps.

1.


Click Start, and then click Search.

2.


In the Search Results pane, click All files and folders under Search 
Companion.

3.


In the All or part of the file name box, type a file name from the 
appropriate file information table, and then click Search.

4.


In the list of files, right-click a file name from the appropriate file 
information table, and then click Properties.

Note Depending on the version of the operating system or programs 
installed, some of the files that are listed in the file information table 
may not be installed.

5.


On the Version tab, determine the version of the file that is installed on 
your computer by comparing it to the version that is documented in the 
appropriate file information table.

Note Attributes other than file version may change during installation. 
Comparing other file attributes to the information in the file information 
table is not a supported method of verifying the update installation. 
Also, in certain cases, files may be renamed during installation. If the 
file or version information is not present, use one of the other available 
methods to verify update installation.


Registry Key Verification

You may also be able to verify the files that this security update has 
installed by reviewing the following registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows 
NT\CurrentVersion\Hotfix\KB841872\File 1

Note This registry key may not contain a complete list of installed files. 
Also, this registry key may not be created correctly when an administrator 
or an OEM integrates or slipstreams the 841872 security update into the 
Windows installation source files.
Top of section
Top of section

Acknowledgments

Microsoft thanks the following for working with us to help protect 
customers:


Rafal Wojtczuk working with McAfee for reporting the POSIX Vulnerability 
(CAN-2004-0210).

Obtaining Other Security Updates:

Updates for other security issues are available from the following 
locations:


Security updates are available from the Microsoft Download Center: You can 
find them most easily by doing a keyword search for "security_patch".


Updates for consumer platforms are available from the Windows Update Web 
site.

Support:


Customers in the U.S. and Canada can receive technical support from 
Microsoft Product Support Services at 1-866-PCSAFETY. There is no charge 
for support calls that are associated with security updates.


International customers can receive support from their local Microsoft 
subsidiaries. There is no charge for support that is associated with 
security updates. For more information about how to contact Microsoft for 
support issues, visit the International Support Web site.

Security Resources:


The Microsoft TechNet Security Web site provides additional information 
about security in Microsoft products.


Microsoft Software Update Services


Microsoft Baseline Security Analyzer (MBSA)


Windows Update


Windows Update Catalog: For more information about the Windows Update 
Catalog, see Microsoft Knowledge Base Article 323166.


Office Update

Software Update Services:

By using Microsoft Software Update Services (SUS), administrators can 
quickly and reliably deploy the latest critical updates and security 
updates to Windows 2000 and Windows Server 2003-based servers, and to 
desktop systems that are running Windows 2000 Professional or Windows XP 
Professional.

For more information about how to deploy this security update with 
Software Update Services, visit the Software Update Services Web site.

Systems Management Server:

Microsoft Systems Management Server (SMS) delivers a highly-configurable 
enterprise solution for managing updates. By using SMS, administrators can 
identify Windows-based systems that require security updates and to 
perform controlled deployment of these updates throughout the enterprise 
with minimal disruption to end users. For more information about how 
administrators can use SMS 2003 to deploy security updates, see the SMS 
2003 Security Patch Management Web site. SMS 2.0 users can also use 
Software Updates Service Feature Pack to help deploy security updates. For 
information about SMS, visit the SMS Web site.

Note SMS uses the Microsoft Baseline Security Analyzer and the Microsoft 
Office Detection Tool to provide broad support for security bulletin 
update detection and deployment. Some software updates may not be detected 
by these tools. Administrators can use the inventory capabilities of the 
SMS in these cases to target updates to specific systems. For more 
information about this procedure, see the following Web site. Some 
security updates require administrative rights following a restart of the 
system. Administrators can use the Elevated Rights Deployment Tool 
(available in the SMS 2003 Administration Feature Pack and in the SMS 2.0 
Administration Feature Pack) to install these updates.

Disclaimer:

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.

Revisions:


V1.0 (July 13, 2004): Bulletin published

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