Microsoft Security Bulletin MS05-028 Vulnerability in Web Client Service Could Allow Remote Code Execution (896426)

Microsoft Security Bulletin MS05-028
Vulnerability in Web Client Service Could Allow Remote Code Execution (896426)

Issued: June 14, 2005
Version: 1.0
Summary

Who should read this document: Customers who use Microsoft Windows

Impact of Vulnerability: Remote Code Execution

Maximum Severity Rating: Important

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

Security Update Replacement: None

Caveats: None

Tested Software and Security Update Download Locations:

Affected Software:
•

Microsoft Windows XP Service Pack 1 – Download the update
•

Microsoft Windows XP 64-Bit Edition Service Pack 1 (Itanium) – Download the update
•

Microsoft Windows XP 64-Bit Edition Version 2003 (Itanium) – Download the update
•

Microsoft Windows Server 2003 – Download the update
•

Microsoft Windows Server 2003 for Itanium-based Systems – Download the update

Non-Affected Software:
•

Microsoft Windows 2000 Service Pack 3 and Microsoft Windows 2000 Service Pack 4
•

Microsoft Windows XP Service Pack 2
•

Microsoft Windows XP Professional x64 Edition
•

Microsoft Windows Server 2003 Service Pack 1
•

Microsoft Windows Server 2003 with SP1 for Itanium-based Systems
•

Microsoft Windows Server 2003 x64 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 whether the versions are affected. Other versions either no longer include security update support or may not be affected. To determine the support life cycle for your product and version, visit the Microsoft Support Lifecycle Web site.
Top of sectionTop of section
General Information

Executive Summary

Executive Summary:

This update resolves a newly-discovered, privately-reported vulnerability. 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. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

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

Severity Ratings and Vulnerability Identifiers:
Vulnerability Identifiers Impact of Vulnerability Windows XP Service Pack 1 Windows Server 2003

Web Client Vulnerability - CAN-2005-1207

Remote Code Execution

Important

Moderate

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.

Note The severity ratings for non-x86 operating system versions map to the x86 operating systems versions as follows:
•

The Microsoft Windows XP 64-Bit Edition Service Pack 1 (Itanium) severity rating is the same as the Windows XP Service Pack 1 severity rating.
•

The Microsoft Windows XP 64-Bit Edition Version 2003 (Itanium) severity rating is the same as the Windows XP Service Pack 1 severity rating.
•

The Microsoft Windows Server 2003 for Itanium-based Systems severity rating is the same as the Windows Server 2003 severity rating.
Top of sectionTop of section

Frequently asked questions (FAQ) related to this security update

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

Can I use Systems Management Server (SMS) to determine whether this update is required?
Yes. SMS can help detect and deploy this security update. For information about SMS, visit the SMS Web site. You can deploy this update by using the Inventory and Software Distribution feature of SMS.
Top of sectionTop of section

Vulnerability Details

Web Client Vulnerability - CAN-2005-1207:

A remote code execution vulnerability exists in the way that Windows processes Web Client requests that could allow an attacker who successfully exploited this vulnerable to take complete control of the affected system.

Mitigating Factors for Web Client Vulnerability - CAN-2005-1207:
•

An attacker must have valid logon credentials to exploit this vulnerability. The vulnerability could not be exploited by anonymous users.
•

By default, the Web Client service is disabled in Windows Server 2003. An administrator would have to manually enable this service for the system to become vulnerable to this issue.
•

Attempts to exploit this vulnerability would most likely result in a denial of service condition.
•

Firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter. Best practices recommend that systems that are connected to the Internet have a minimal number of ports exposed. By default, the Internet Connection Firewall that is provided as part of Windows XP Service Pack 1 and Windows Server 2003 blocks the affected ports from responding to network-based attempts to exploit this vulnerability.
•

The Windows Server 2003 Security Guide recommends disabling the Web Client service. Environments that comply with these guidelines would be at a reduced risk from this vulnerability.
Top of sectionTop of section

Workarounds for Web Client Vulnerability - CAN-2005-1207:

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 in the following section.
•

Disable the Web Client service

Disabling the Web Client service will help protect the affected system from attempts to exploit this vulnerability. To disable the Web Client service, follow these steps:

Click Start, and then click Control Panel. Alternatively, point to Settings, and then click Control Panel.

Double-click Administrative Tools.

Double-click Services.

Double-click WebClient.

In the Startup type list, click Disabled.

Click Stop, and then click OK.

You can also stop and disable the Web Client service by using the following command at the command prompt:

sc stop WebClient & sc config WebClient start= disabled

Impact of Workaround: If the Web Client service is disabled, Web Distributed Authoring and Versioning (WebDAV) requests are not transmitted. If the Web Client service is disabled, any services that explicitly depend on the Web Client service will not start, and an error message will be logged in the System log. Windows Server 2003 users will not be able to use the "Open as Web Folder" functionality.
•

Use the Group Policy settings to disable the WebClient service on all affected systems that do not require this feature.
Because the Web Client service is a possible attack vector, disable the service by using the Group Policy settings. You can disable the startup of this service at either the local, site, domain, or organizational-unit level by using Group Policy object functionality in Windows 2000 domain environments or in Windows Server 2003 domain environments.

Note You may also review the Windows Server 2003 Security Guide. This guide includes information about how to disable services.

For more information about Group Policy, visit the following Microsoft Web sites:
•

Step-by-Step Guide to Understanding the Group Policy Feature Set
•

Windows 2000 Group Policy
•

Group Policy in Windows Server 2003

Impact of Workaround: If the Web Client service is disabled, Web Distributed Authoring and Versioning (WebDAV) requests are not transmitted. If the Web Client service is disabled, any services that explicitly depend on the Web Client service will not start, and an error message will be logged in the System log. Windows Server 2003 users will not be able to use the "Open as Web Folder" functionality.
•

Block TCP ports 139 and 445 at the firewall:

Although WebDAV uses TCP port 80 for outbound communication, TCP ports 139 and 445 can be used inbound to attempt to connect to this service and try to exploit this vulnerability. Blocking them at the firewall can help prevent systems that are behind that firewall from attempts to exploit this vulnerability. We recommend that you block all unsolicited inbound communication from the Internet to help prevent attacks that may use other ports. For more information about ports, visit the following Web site.
•

To help protect from network-based attempts to exploit this vulnerability, use a personal firewall, such as the Internet Connection Firewall, which is included with Windows XP and with Windows Server 2003.

By default, the Internet Connection Firewall feature in Windows XP and in Windows Server 2003 helps protect your Internet connection by blocking unsolicited incoming traffic. We recommend that you block all unsolicited incoming communication from the Internet.

To enable the Internet Connection Firewall feature by using the Network Setup Wizard, follow these steps:

Click Start, and then click Control Panel.

In the default Category View, click Network and Internet Connections, and then click Setup or change your home or small office network. The Internet Connection Firewall feature is enabled when you select a configuration in the Network Setup Wizard that indicates that your system is connected directly to the Internet.

To configure Internet Connection Firewall manually for a connection, follow these steps:

Click Start, and then click Control Panel.

In the default Category View, click Networking and Internet Connections, and then click Network Connections.

Right-click the connection on which you want to enable Internet Connection Firewall, and then click Properties.

Click the Advanced tab.

Click to select the Protect my computer or network by limiting or preventing access to this computer from the Internet check box, and then click OK.

Note If you want to enable certain programs and services to communicate through the firewall, click Settings on the Advanced tab, and then select the programs, the protocols, and the services that are required.
•

To help protect from network-based attempts to exploit this vulnerability, enable advanced TCP/IP filtering on systems that support this feature.

You can enable advanced TCP/IP filtering to block all unsolicited inbound traffic. For more information about how to configure TCP/IP filtering, see Microsoft Knowledge Base Article 309798.
•

To help protect from network-based attempts to exploit this vulnerability, block the affected ports by using IPSec on the affected systems.

Use Internet Protocol security (IPSec) to help protect network communications. Detailed information about IPSec and about how to apply filters is available in Microsoft Knowledge Base Article 313190 and Microsoft Knowledge Base Article 813878.
Top of sectionTop of section

FAQ for Web Client Vulnerability - CAN-2005-1207:

What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To attempt to exploit the vulnerability, an attacker must have valid logon credentials. The vulnerability could not be exploited by anonymous users. An attacker could also use this vulnerability to perform a local elevation of privilege attack.

What causes the vulnerability?
An unchecked buffer in the WebClient service.

What is the Web Client service?
The Web Client service allows applications to access documents on the Internet. Web Client extends the networking capability of Windows by allowing standard Win32 applications to create, read, and write files on Internet file servers by using the WebDAV protocol. The WebDAV protocol is a file-access protocol that is described in XML and that travels over the Hypertext Transfer Protocol (HTTP). By using standard HTTP, WebDAV runs over the existing Internet infrastructure. For example, WebDAV runs over firewalls and routers.

If the Web Client service is stopped, you will be prevented from using the Web Publishing Wizard to publish data to the Internet for locations that use the WebDAV protocol. If this service is disabled, any services that explicitly depend on this service will not start. For more information on WebDAV, see the following product documentation.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

Who could exploit the vulnerability?
To attempt to exploit the vulnerability, an attacker must have valid logon credentials. The vulnerability could not be exploited by anonymous users. Even though the Web Client service is used to support the WebDAV protocol over the Internet, an authenticated attacker must perform the steps that are required to attempt to exploit this issue. If the Guest account has been enabled on an affected system, then this attack could be performed by any user.

How could an attacker exploit the vulnerability?
There are several different ways that an attacker could try to exploit this vulnerability. An attacker would first have to authenticate to the system. An attacker could then try to exploit the vulnerability directly over a network by creating a series of specially crafted messages and sending them to an affected system. The messages could then cause the affected system to execute code.

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 either locally or remotely.

What systems are primarily at risk from the vulnerability?
All affected operating systems are at risk from this vulnerability. By default, the Internet Connection Firewall that is provided as part of Windows XP Service Pack 1 and Windows Server 20003 blocks the affected ports from responding to network-based attempts to exploit this vulnerability. By default, the Web Client service is disabled in Windows Server 2003.

Could the vulnerability be exploited over the Internet?
Yes. An attacker could try to exploit this vulnerability over the Internet. Firewall best practices and standard default firewall configurations can help protect against attacks that originate from the Internet. Microsoft has provided information about how you can help protect your PC. End users can visit the Protect Your PC Web site. IT professionals can visit the Security Center Web site.

What does the update do?
The update removes the vulnerability by modifying the way that the Web Client service 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 to indicate 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 to indicate 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 sectionTop of section
Top of sectionTop of section
Top of sectionTop of section

Security Update Information

Affected Software:

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

Windows Server 2003 (all versions)

Prerequisites
This security update requires the originally released version of Windows Server 2003.

Inclusion in Future Service Packs:
The update for this issue is included in Service Pack 1.

Installation Information

This security update supports the following setup switches.
Supported Security Update Installation Switches
Switch Description

/help

Displays the command-line options
Setup Modes

/passive

Unattended Setup mode. No user interaction is required, but installation status is displayed. If a restart is required at the end of Setup, a dialog box will be presented to the user with a timer warning that the computer will restart in 30 seconds.

/quiet

Quiet mode. This is the same as unattended mode, but no status or error messages are displayed.
Restart Options

/norestart

Does not restart when installation has completed

/forcerestart

Restarts the computer after installation and force other applications to close at shutdown without saving open files first.

/warnrestart[:x]

Presents a dialog box with a timer warning the user that the computer will restart in x seconds. (The default setting is 30 seconds.) Intended for use with the /quiet switch or the /passive switch.

/promptrestart

Display a dialog box prompting the local user to allow a restart
Special Options

/overwriteoem

Overwrites OEM files without prompting

/nobackup

Does not backup files needed for uninstall

/forceappsclose

Forces other programs to close when the computer shuts down

/log:path

Allows the redirection of installation log files

/integrate:path

Integrates the update into the Windows source files. These files are located at the path that is specified in the switch.

/extract[:path]

Extracts files without starting the Setup program

/ER

Enables extended error reporting

/verbose

Enables verbose logging. During installation, creates %Windir%\CabBuild.log. This log details the files that are copied. Using this switch may cause the installation to proceed more slowly.

Note You can combine these switches into one command. For backward compatibility, the security update also supports many of the setup switches that the earlier version of the Setup program uses. For more information about the supported installation switches, see Microsoft Knowledge Base Article 262841. For more information about the Update.exe installer, visit the Microsoft TechNet Web site.

Deployment Information

To install the security update without any user intervention, use the following command at a command prompt for Windows Server 2003:

Windowsserver2003-kb896426-x86-enu /quiet

Note Use of the /quiet switch will suppress all messages. This includes suppressing failure messages. Administrators should use one of the supported methods to verify the installation was successful when they use the /quiet switch. Administrators should also review the KB896426.log file for any failure messages when they use this switch.

To install the security update without forcing the system to restart, use the following command at a command prompt for Windows Server 2003:

Windowsserver2003-kb896426-x86-enu /norestart

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

Restart Requirement

You must restart your system after you apply this security update. For more information about the reasons why you may be prompted to restart your computer, see Microsoft Knowledge Base Article 887012.

Removal Information

To remove this 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%\$NTUninstallKB896426$\Spuninst folder.
Supported Spuninst.exe Switches
Switch Description

/help

Displays the command-line options
Setup Modes

/passive

Unattended Setup mode. No user interaction is required, but installation status is displayed. If a restart is required at the end of Setup, a dialog box will be presented to the user with a timer warning that the computer will restart in 30 seconds.

/quiet

Quiet mode. This is the same as unattended mode, but no status or error messages are displayed.
Restart Options

/norestart

Does not restart when installation has completed

/forcerestart

Restarts the computer after installation and force other applications to close at shutdown without saving open files first.

/warnrestart[:x]

Presents a dialog box with a timer warning the user that the computer will restart in x seconds. (The default setting is 30 seconds.) Intended for use with the /quiet switch or the /passive switch.

/promptrestart

Display a dialog box prompting the local user to allow a restart
Special Options

/forceappsclose

Forces other programs to close when the computer shuts down

/log:path

Allows the redirection of installation log files

File Information

The English version of this security update has the file attributes 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.

Windows Server 2003, Web Edition; Windows Server 2003, Standard Edition; Windows Server 2003, Enterprise Edition; Windows Server 2003, Datacenter Edition; and Windows Small Business Server 2003:
File Name Version Date Time Size Folder

Mrxdav.sys

5.2.3790.316

22-Apr-2005

18:49

181,248

RTMGDR

Webclnt.dll

5.2.3790.316

25-Apr-2005

18:48

69,120

RTMGDR

Mrxdav.sys

5.2.3790.316

22-Apr-2005

18:56

181,760

RTMQFE

Webclnt.dll

5.2.3790.316

25-Apr-2005

18:40

69,120

RTMQFE

Windows Server 2003, Enterprise Edition for Itanium-based Systems and Windows Server 2003, Datacenter Edition for Itanium-based Systems:
File Name Version Date Time Size CPU Folder

Mrxdav.sys

5.2.3790.316

22-Apr-2005

18:47

526,848

IA-64

RTMGDR

Webclnt.dll

5.2.3790.316

25-Apr-2005

18:46

211,968

IA-64

RTMGDR

Wwebclnt.dll

5.2.3790.316

25-Apr-2005

18:48

69,120

x86

RTMGDR\WOW

Mrxdav.sys

5.2.3790.316

22-Apr-2005

18:38

529,408

IA-64

RTMQFE

Webclnt.dll

5.2.3790.316

25-Apr-2005

18:36

211,968

IA-64

RTMQFE

Wwebclnt.dll

5.2.3790.316

25-Apr-2005

18:40

69,120

x86

RTMQFE\WOW

Note When you install this security update on Windows Server 2003, the installer checks to see if one or more of the files that are being updated on your system have previously been updated by a Microsoft hotfix. If you have previously installed a hotfix to update an affected file, the installer copies the RTMQFE files to your system. Otherwise, the installer copies the RTMGDR files to your system.

For more information about this behavior, see Microsoft Knowledge Base Article 824994.

For more information about the Update.exe installer, visit the Microsoft TechNet Web site.

For more information about the terminology that appears in this bulletin, such as hotfix, see Microsoft Knowledge Base Article 824684.

Verifying that the Update Has Been Applied
•

Microsoft Baseline Security Analyzer

To verify that a security update has been applied to an affected system, you may be able to use the Microsoft Baseline Security Analyzer (MBSA) tool. MBSA 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.

Click Start, and then click Search.

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

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

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.

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 the 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 that the update has been applied. 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 keys.

Windows Server 2003, Web Edition; Windows Server 2003, Standard Edition; Windows Server 2003, Enterprise Edition; Windows Server 2003, Datacenter Edition; Windows Small Business Server 2003; Windows Server 2003, Enterprise Edition for Itanium-based Systems; and Windows Server 2003, Datacenter Edition for Itanium-based Systems:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows Server 2003\SP1\KB896426\Filelist

Note This registry key may not contain a complete list of installed files. Also, this registry key may not be created correctly if an administrator or an OEM integrates or slipstreams the 896426 security update into the Windows installation source files.
Top of sectionTop of section

Windows XP (all versions)

Prerequisites
This security update requires Microsoft Windows XP Service Pack 1. For more information, see Microsoft Knowledge Base Article 322389.

Inclusion in Future Service Packs:
The update for this issue is included in Windows XP Service Pack 2.

Installation Information

This security update supports the following setup switches.
Supported Security Update Installation Switches
Switch Description

/help

Displays the command-line options
Setup Modes

/passive

Unattended Setup mode. No user interaction is required, but installation status is displayed. If a restart is required at the end of Setup, a dialog box will be presented to the user with a timer warning that the computer will restart in 30 seconds.

/quiet

Quiet mode. This is the same as unattended mode, but no status or error messages are displayed.
Restart Options

/norestart

Does not restart when installation has completed

/forcerestart

Restarts the computer after installation and force other applications to close at shutdown without saving open files first.

/warnrestart[:x]

Presents a dialog box with a timer warning the user that the computer will restart in x seconds. (The default setting is 30 seconds.) Intended for use with the /quiet switch or the /passive switch.

/promptrestart

Display a dialog box prompting the local user to allow a restart
Special Options

/overwriteoem

Overwrites OEM files without prompting

/nobackup

Does not backup files needed for uninstall

/forceappsclose

Forces other programs to close when the computer shuts down

/log:path

Allows the redirection of installation log files

/integrate:path

Integrates the update into the Windows source files. These files are located at the path that is specified in the switch.

/extract[:path]

Extracts files without starting the Setup program

/ER

Enables extended error reporting

/verbose

Enables verbose logging. During installation, creates %Windir%\CabBuild.log. This log details the files that are copied. Using this switch may cause the installation to proceed more slowly.

Note You can combine these switches into one command. For backward compatibility, the security update also supports the setup switches that the earlier version of the Setup program uses. For more information about the supported installation switches, see Microsoft Knowledge Base Article 262841. For more information about the Update.exe installer, visit the Microsoft TechNet Web site.

Deployment Information

To install the security update without any user intervention, use the following command at a command prompt for Microsoft Windows XP:

Windowsxp-kb896426-x86-enu /quiet

Note Use of the /quiet switch will suppress all messages. This includes suppressing failure messages. Administrators should use one of the supported methods to verify the installation was successful when they use the /quiet switch. Administrators should also review the KB896426.log file for any failure messages when they use this switch.

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

Windowsxp-kb896426-x86-enu /norestart

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

Restart Requirement

You must restart your system after you apply this security update. For more information about the reasons why you may be prompted to restart your computer, see Microsoft Knowledge Base Article 887012.

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%\$NTUninstallKB896426$\Spuninst folder.
Supported Spuninst.exe Switches
Switch Description

/help

Displays the command-line options
Setup Modes

/passive

Unattended Setup mode. No user interaction is required, but installation status is displayed. If a restart is required at the end of Setup, a dialog box will be presented to the user with a timer warning that the computer will restart in 30 seconds.

/quiet

Quiet mode. This is the same as unattended mode, but no status or error messages are displayed.
Restart Options

/norestart

Does not restart when installation has completed

/forcerestart

Restarts the computer after installation and force other applications to close at shutdown without saving open files first.

/warnrestart[:x]

Presents a dialog box with a timer warning the user that the computer will restart in x seconds. (The default setting is 30 seconds.) Intended for use with the /quiet switch or the /passive switch.

/promptrestart

Display a dialog box prompting the local user to allow a restart
Special Options

/forceappsclose

Forces other programs to close when the computer shuts down

/log:path

Allows the redirection of installation log files

File Information

The English version of this security update has the file attributes 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.

Windows XP Home Edition Service Pack 1, Windows XP Professional Service Pack 1, Windows XP Tablet PC Edition, and Windows XP Media Center Edition:
File Name Version Date Time Size Folder

Mrxdav.sys

5.1.2600.1673

26-Apr-2005

01:58

173,312

SP1QFE

Webclnt.dll

5.1.2600.1673

26-Apr-2005

06:29

62,976

SP1QFE

Windows XP 64-Bit Edition Service Pack 1 (Itanium):
File Name Version Date Time Size CPU Folder

Mrxdav.sys

5.1.2600.1673

26-Apr-2005

01:50

550,016

IA-64

SP1QFE

Webclnt.dll

5.1.2600.1673

26-Apr-2005

06:28

211,456

IA-64

SP1QFE

Wwebclnt.dll

5.1.2600.1673

26-Apr-2005

06:29

62,976

x86

SP1QFE\WOW

Windows XP 64-Bit Edition Version 2003 (Itanium):
File Name Version Date Time Size CPU Folder

Mrxdav.sys

5.2.3790.316

22-Apr-2005

18:47

526,848

IA-64

RTMGDR

Webclnt.dll

5.2.3790.316

25-Apr-2005

18:46

211,968

IA-64

RTMGDR

Wwebclnt.dll

5.2.3790.316

25-Apr-2005

18:48

69,120

x86

RTMGDR\WOW

Mrxdav.sys

5.2.3790.316

22-Apr-2005

18:38

529,408

IA-64

RTMQFE

Webclnt.dll

5.2.3790.316

25-Apr-2005

18:36

211,968

IA-64

RTMQFE

Wwebclnt.dll

5.2.3790.316

25-Apr-2005

18:40

69,120

x86

RTMQFE\WOW

Notes When you install these security updates, the installer checks to see if one or more of the files that are being updated on your system have previously been updated by a Microsoft hotfix.

If you have previously installed a hotfix to update one of these files, the installer copies the RTMQFE files to your system. Otherwise, the installer copies the RTMGDR files to your system.

For more information about this behavior, see Microsoft Knowledge Base Article 824994.

For more information about the Update.exe installer, visit the Microsoft TechNet Web site.

For more information about the terminology that appears in this bulletin, such as hotfix, see Microsoft Knowledge Base Article 824684.

Note For Windows XP 64-Bit Edition Version 2003 (Itanium), this security update is the same as the Windows Server 2003 for Itanium-based Systems security update.

Verifying that the Update Has Been Applied
•

Microsoft Baseline Security Analyzer

To verify that a security update has been applied to an affected system, you may be able to use the Microsoft Baseline Security Analyzer (MBSA) tool. MBSA 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.

Click Start, and then click Search.

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

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

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.

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 the 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 that the update has been applied. 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 keys.

For Windows XP Home Edition Service Pack 1, Windows XP Professional Service Pack 1, Windows XP Tablet PC Edition, Windows XP Media Center Edition, and Windows XP Home:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP2\KB896426\Filelist

For Windows XP 64-Bit Edition Version 2003 (Itanium):

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows Server 2003\SP1\KB896426\Filelist

Note These registry keys may not contain a complete list of installed files. Also, these registry keys may not be created correctly if an administrator or an OEM integrates or slipstreams the 896426 security update into the Windows installation source files.
Top of sectionTop of section
Top of sectionTop of section

Acknowledgments

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

Mark Litchfield with Next Generation Security Software Ltd. for reporting the Web Client Vulnerability (CAN-2005-1207).

Obtaining Other Security Updates:

Updates for other security issues are available at the following locations:
•

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

Updates for consumer platforms are available at 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 by using 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 can 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, visit 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 Analyze, Microsoft Office Detection Tool, and the Enterprise Update Scanning 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, visit 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 (June 14, 2005): Bulletin published