Q-270: Vulnerability in Server Service

Executive Summary

Executive Summary:

This update resolves a privately disclosed vulnerability as well as additional issues discovered through internal investigations.

An attacker who successfully exploited the 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 immediately

Severity Ratings and Vulnerability Identifiers:

Vulnerability Identifiers	Impact of Vulnerability	Windows 2000	Windows XP Service Pack 1	Windows XP Service Pack 2	Windows Server 2003	Windows Server 2003 Service Pack 1
Buffer Overrun in Server Service Vulnerability - CVE-2006-3439	Remote Code Execution	Critical	Critical	Critical	Critical	Critical
Aggregate Severity of All Vulnerabilities		Critical	Critical	Critical	Critical	Critical

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 security updates for Windows Server 2003, Windows Server 2003 Service Pack 1, and Windows Server 2003 x64 Edition also apply to Windows Server 2003 R2.

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

•	The Windows XP Professional x64 Edition severity rating is the same as the Windows Server 2003 Service Pack 1
•	The Windows Server 2003 and Windows Server 2003 Service Pack 1 for Itanium-based Systems severity rating are the same as the Windows Server 2003 severity rating.
•	The Windows Server 2003 x64 Edition severity rating is the same as the Windows Server 2003 Service Pack 1 severity rating.

Top of section

Frequently Asked Questions (FAQ) Related to This Security Update

Extended security update support for Microsoft Windows 98, Windows 98 Second Edition, or Windows Millennium Edition ended on July 11, 2006. I am still using one of these operating systems; what should I do?
Windows 98, Windows 98 Second Edition, and Windows Millennium Edition have reached the end of their support life cycles. It should be a priority for customers who have these operating system versions to migrate to supported versions to prevent potential exposure to vulnerabilities. For more information about the Windows Product Lifecycle, 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 Microsoft Product Support Services Web site.

Extended security update support for Microsoft Windows NT Workstation 4.0 Service Pack 6a and Windows 2000 Service Pack 2 ended on June 30, 2004. Extended security update support for Microsoft Windows NT Server 4.0 Service Pack 6a ended on December 31, 2004. Extended security update support for Microsoft Windows 2000 Service Pack 3 ended on June 30, 2005. I am still using one of these operating systems; what should I do?
Windows NT Workstation 4.0 Service Pack 6a, Windows NT Server 4.0 Service Pack 6a, Windows 2000 Service Pack 2, and Windows 2000 Service Pack 3 have reached the end of their support life cycles. It should be a priority for customers who have these operating system versions to migrate to supported versions to prevent potential exposure to vulnerabilities. For more information about the Windows Product Lifecycle, 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 Microsoft Product Support Services Web site.

Customers who require custom support for these products 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 telephone numbers. When you call, ask to speak with the local Premier Support sales manager. For more information, see the Windows Operating System Product Support Lifecycle FAQ.

For more information, visit the Windows Operating System FAQ.

Can I use the Microsoft Baseline Security Analyzer (MBSA) to determine whether this update is required?
The following table provides the MBSA detection summary for this security update.

Product	MBSA 1.2.1	MBSA 2.0
Microsoft Windows 2000 Service Pack 4	Yes	Yes
Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2	Yes	Yes
Microsoft Windows XP Professional x64 Edition	No	Yes
Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1	Yes	Yes
Microsoft Windows Server 2003 for Itanium-based Systems and Microsoft Windows Server 2003 with Service Pack 1 for Itanium-based Systems	No	Yes
Microsoft Windows Server 2003 x64 Edition family	No	Yes

For more information about MBSA, visit the MBSA Web site. For more information about the programs that Microsoft Update and MBSA 2.0 currently do not detect, see Microsoft Knowledge Base Article 895660.

For more detailed information, see Microsoft Knowledge Base Article 910723.

For more information about MBSA, visit the MBSA Web site.

For more information about the programs that Microsoft Update and MBSA 2.0 currently do not detect, see Microsoft Knowledge Base Article 895660.

For more detailed information, see Microsoft Knowledge Base Article 910723.

What is the Enterprise Update Scan Tool (EST)?
As part of an ongoing commitment to provide detection tools for bulletin-class security updates, Microsoft delivers a stand-alone detection tool whenever the Microsoft Baseline Security Analyzer (MBSA) and the Office Detection Tool (ODT) cannot detect whether the update is required for an MSRC release cycle. This stand-alone tool is called the Enterprise Update Scan Tool (EST) and is designed for enterprise administrators. When a version of the Enterprise Update Scan Tool is created for a specific bulletin, customers can run the tool from a command-line interface (CLI) and view the results of the XML output file. To help customers better utilize the tool, detailed documentation will be provided with the tool. There is also a version of the tool that offers an integrated experience for SMS administrators.

Can I use Systems Management Server (SMS) to determine whether this update is required?
The following table provides the SMS detection summary for this security update.

Product	SMS 2.0	SMS 2003
Microsoft Windows 2000 Service Pack 4	Yes	Yes
Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2	Yes	Yes
Microsoft Windows XP Professional x64 Edition	No	Yes
Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1	Yes	Yes
Microsoft Windows Server 2003 for Itanium-based Systems and Microsoft Windows Server 2003 with Service Pack 1 for Itanium-based Systems	No	Yes
Microsoft Windows Server 2003 x64 Edition family	No	Yes

SMS uses MBSA for detection. Therefore, SMS has the same limitation that is listed earlier in this bulletin related to programs that MBSA does not detect.

Top of section

Vulnerability Details

Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

There is a remote code execution vulnerability in Server Service that could allow an attacker who successfully exploited this vulnerability to take complete control of the affected system.

Mitigating Factors for Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

Workarounds for Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

Microsoft has tested the following workarounds. Although 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.

•

Block TCP ports 139 and 445 at the firewall:

This port is used to initiate a connection with the affected component. Blocking TCP ports 139 and 445 at the firewall will help protect 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. In Windows XP Service Pack 2 this feature is called the Windows Firewall.

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

1.	Click Start, and then click Control Panel.
2.	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:

1.	Click Start, and then click Control Panel.
2.	In the default Category View, click Networking and Internet Connections, and then click Network Connections.
3.	Right-click the connection on which you want to enable Internet Connection Firewall, and then click Properties.
4.	Click the Advanced tab.
5.	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 section

FAQ for Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could remotely 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.

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

What is the Server service?
The Server service provides RPC support, file print support and named pipe sharing over the network. The Server service allows the sharing of your local resources (such as disks and printers) so that other users on the network can access them. It also allows named pipe communication between applications running on other computers and your computer, which is used for RPC.

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?
Any anonymous user who could deliver a specially crafted message to the affected system could try to exploit this vulnerability.

How could an attacker exploit the vulnerability?
An attacker could try to exploit the vulnerability by creating a specially crafted message and sending the message to an affected system. The message could then cause the affected system to execute code.

What systems are primarily at risk from the vulnerability?
While all workstations and servers are at risk regarding this issue, Windows 2000 systems are primarily at risk due to the unique characteristics of the vulnerability and affected code path.

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 Guidance Center Web site.

What does the update do?
The update removes the vulnerability by modifying the way that Server service validates the length of a message it receives in RPC communications 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.

When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
Yes. When the security bulletin was released, Microsoft had received information that this vulnerability was being exploited.

Does applying this security update help protect customers from the code that has been published publicly that attempts to exploit this vulnerability?
Yes. This security update addresses the vulnerability that is currently being exploited. The vulnerability that has been addressed has been assigned the Common Vulnerability and Exposure number CVE-2006-3439.

How does this vulnerability relate to the vulnerability that is corrected by MS06-035?
While both vulnerabilities were in Server service this update addresses a new vulnerability that was not addressed as part of MS06-035. MS06-035 helps protect against the vulnerability that is discussed in that bulletin, but does not address this new vulnerability. This update does not replace MS06-035. You must install this update and the update that is provided as part of the MS06-035 security bulletin to help protect your system against both vulnerabilities.

Top 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 Windows Server 2003 or Windows Server 2003 Service Pack 1.

Note The security updates for Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1 also apply to Microsoft Windows Server 2003 R2.

Inclusion in Future Service Packs:
The update for this issue will be included in future Service Pack or Update Rollup.

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 forces other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Displays 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 back up files needed for uninstallation.
/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-kb921883-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 KB921883.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-kb921883-x86-enu /norestart

For information about how to deploy this security update by using Software Update Services, visit the Software Update Services Web site. For more information about how to deploy this security update using Windows Server Update Services, visit the Windows Server Update Services Web site. This security update will also be available through the Microsoft Update Web site.

Restart Requirement

You must restart your system after you apply this security update.

This security update does not support HotPatching. For more information about HotPatching and how to deploy this security update as a HotPatch see Microsoft Knowledge Base Article 897341.

Note Not all security updates support HotPatching, and some security updates that support HotPatching might require that you restart the server after you install the security update. HotPatching is only supported if the files being replaced by the security update are General Distribution Release (GDR) files. For more information about this behavior, see Microsoft Knowledge Base Article 897341 and Microsoft Knowledge Base Article 824994.

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%\$NTUninstallKB921883$\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 forces other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Displays 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, Datacenter Edition; Windows Server 2003, Enterprise Edition; Windows Small Business Server 2003; Windows Server 2003, Web Edition with SP1; Windows Server 2003, Standard Edition with SP1; Windows Server 2003, Enterprise Edition with SP1; Windows Server 2003, Datacenter Edition with SP1; Windows Server 2003 R2, Web Edition; Windows Server 2003 R2, Standard Edition; Windows Server 2003 R2, Datacenter Edition; Windows Server 2003 R2, Enterprise Edition; Windows Small Business Server 2003 R2:

File Name	Version	Date	Time	Size	CPU	Folder
Netapi32.dll	5.2.3790.559	17-Jul-2006	09:38	324,608	x86	RTMGDR
Netapi32.dll	5.2.3790.559	17-Jul-2006	09:56	324,608	x86	RTMQFE
Netapi32.dll	5.2.3790.2747	17-Jul-2006	09:51	349,696	x86	SP1GDR
Netapi32.dll	5.2.3790.2747	17-Jul-2006	10:12	349,696	x86	SP1QFE

Windows Server, 2003 Enterprise Edition for Itanium-based Systems; Windows Server 2003, Datacenter Edition for Itanium-based Systems; Windows Server 2003, Enterprise Edition with SP1 for Itanium-based Systems; and Windows Server 2003, Datacenter Edition with SP1 for Itanium-based Systems:

File Name	Version	Date	Time	Size	CPU	Folder
Netapi32.dll	5.2.3790.559	17-Jul-2006	10:30	851,968	IA-64	RTMGDR
Wnetapi32.dll	5.2.3790.559	17-Jul-2006	10:30	324,608	x86	RTMGDR\WOW
Netapi32.dll	5.2.3790.559	17-Jul-2006	10:31	852,480	IA-64	RTMQFE
Wnetapi32.dll	5.2.3790.559	17-Jul-2006	10:31	324,608	x86	RTMQFE\WOW
Netapi32.dll	5.2.3790.2747	17-Jul-2006	10:33	906,752	IA-64	SP1GDR
Wnetapi32.dll	5.2.3790.2747	17-Jul-2006	10:33	349,696	x86	SP1GDR\WOW
Netapi32.dll	5.2.3790.2747	17-Jul-2006	10:31	906,752	IA-64	SP1QFE
Wnetapi32.dll	5.2.3790.2747	17-Jul-2006	10:31	349,696	x86	SP1QFE\WOW

Windows Server 2003, Standard x64 Edition; Windows Server 2003, Enterprise x64 Edition; and Windows Server 2003, Datacenter x64 Edition; Windows Server 2003 R2, Standard x64 Edition; Windows Server 2003 R2, Enterprise x64 Edition; and Windows Server 2003 R2, Datacenter x64 Edition:

File Name	Version	Date	Time	Size	CPU	Folder
Netapi32.dll	5.2.3790.559	17-Jul-2006	09:38	324,608	x86	RTMGDR
Netapi32.dll	5.2.3790.559	17-Jul-2006	09:56	324,608	x86	RTMQFE
Netapi32.dll	5.2.3790.2747	17-Jul-2006	09:51	349,696	x86	SP1GDR
Netapi32.dll	5.2.3790.2747	17-Jul-2006	10:12	349,696	x86	SP1QFE

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, SP1QFE, or SP2QFE files to your system. Otherwise, the installer copies the RTMGDR, SP1GDR, or SP2GDR files to your system. Security updates may not contain all variations of these files. 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 can 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.

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 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, Web Edition with SP1; Windows Server 2003, Standard Edition with SP1; Windows Server 2003, Enterprise Edition with SP1; Windows Server 2003, Datacenter Edition with SP1; Windows Server 2003, Enterprise Edition for Itanium-based Systems; Windows Server 2003, Datacenter Edition for Itanium-based Systems; Windows Server 2003, Enterprise Edition with SP1 for Itanium-based Systems; Windows Server 2003, Datacenter Edition with SP1 for Itanium-based Systems; Windows Server 2003, Standard x64 Edition; Windows Server 2003, Enterprise x64 Edition; and Windows Server 2003, Datacenter x64 Edition:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows Server 2003\SP2\KB921883\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 security update into the Windows installation source files.

Top of section

Windows XP (all versions)

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

Inclusion in Future Service Packs:
The update for this issue will be included in a future Service Pack or Update Rollup.

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 forces other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Displays 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 back up files needed for uninstallation.
/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-kb921883-x86-enu /quiet

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

Windowsxp-kb921883-x86-enu /norestart

Restart Requirement

You must restart your system after you apply this security update.

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%\$NTUninstallKB921883$\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 forces other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Displays 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

Windows XP Home Edition Service Pack 1, Windows XP Professional Service Pack 1, Windows XP Tablet PC Edition, Windows XP Media Center Edition, Windows XP Home Edition Service Pack 2, Windows XP Professional Service Pack 2, Windows XP Tablet PC Edition 2005, and Windows XP Media Center Edition 2005:

File Name	Version	Date	Time	Size	CPU	Folder
Netapi32.dll	5.1.2600.1874	14-Jul-2006	15:53	307,200	x86	SP1QFE
Netapi32.dll	5.1.2600.2952	14-Jul-2006	15:31	332,288	x86	SP2GDR
Netapi32.dll	5.1.2600.2952	14-Jul-2006	15:41	336,896	x86	SP2QFE

Windows XP Professional x64:

File Name	Version	Date	Time	Size	CPU	Folder
Netapi32.dll	5.2.3790.2747	17-Jul-2006	10:32	603,136	x64	SP1GDR
Wnetapi32.dll	5.2.3790.2747	17-Jul-2006	10:32	349,696	x86	SP1GDR\WOW
Netapi32.dll	5.2.3790.2747	17-Jul-2006	10:27	603,136	x64	SP1QFE
Wnetapi32.dll	5.2.3790.2747	17-Jul-2006	10:27	349,696	x86	SP1QFE\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.

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

•

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 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, Windows XP Home Edition Service Pack 2, Windows XP Professional Service Pack 2, Windows XP Tablet PC Edition 2005, and Windows XP Media Center Edition 2005:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP3\KB921883\Filelist

For Windows XP Professional x64 Edition:

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 security update into the Windows installation source files.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows Server 2003\SP2\KB921883\Filelist

Top of section

Windows 2000 (all versions)

Prerequisites
For Windows 2000, this security update requires Service Pack 4 (SP4). For Small Business Server 2000, this security update requires Small Business Server 2000 Service Pack 1a (SP1a) or Small Business Server 2000 running with Windows 2000 Server Service Pack 4 (SP4).

The software that is listed 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.

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 may be included in a future Update Rollup.

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 forces other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Displays 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 back up files needed for uninstallation.
/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.

Deployment Information

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

Windows2000-kb921883-x86-enu /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 4:

Windows2000-kb921883-x86-enu /norestart

For more information about how to deploy this security update with Software Update Services, visit the Software Update Services Web site. For more information about how to deploy this security update using Windows Server Update Services, visit the Windows Server Update Services Web site. This security update will also be available through the Microsoft Update Web site.

Restart Requirement

You must restart your system after you apply this security update.

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%\$NTUninstallKB921883$\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 forces other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Displays 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

Windows 2000 Service Pack 4 and Small Business Server 2000:

File Name	Version	Date	Time	Size	CPU
Netapi32.dll	5.0.2195.7105	15-Jul-2006	02:25	309,520	x86

Verifying that the Update Has Been Applied

•

Microsoft Baseline Security Analyzer

•

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 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 key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows 2000\SP5\KB921883\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 security update into the Windows installation source files.

Top of section

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 security updates by using Software Update Services, visit the Software Update Services Web site.

By using Windows Server Update Services (WSUS), administrators can quickly and reliably deploy the latest critical updates and security updates for Windows 2000 operating systems and later, Office XP and later, Exchange Server 2003, and SQL Server 2000 onto Windows 2000 and later operating systems.

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 Analyzer, the Microsoft Office Detection Tool, and the Enterprise Update Scan 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.

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.


PROBLEM:	There is a buffer overrun in Server Service.
PLATFORM:	Microsoft Windows 2000 Service Pack 4 Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2 Microsoft Windows XP Professional x64 Edition Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1 Microsoft Windows Server 2003 for Itanium-based Systems and Microsoft Windows Server 2003 with SP1 for Itanium-based Systems Microsoft Windows Server 2003 x64 Edition
DAMAGE:	Could allow an attacker who successfully exploited this vulnerability to take complete control of the affected system.
SOLUTION:	Upgrade to the appropriate version.

VULNERABILITY ASSESSMENT:	The risk is HIGH. Could allow an attacker who successfully exploited this vulnerability to take complete control of the affected system.

LINKS:
CIAC BULLETIN:	http://www.ciac.org/ciac/bulletins/q-270.shtml
ORIGINAL BULLETIN:	Microsoft Security Bulletin MS06-040
ADDITIONAL LINKS:	Cisco Security Response, Document ID: 70997 http://www.cisco.com/en/US/products/ps6120/tsd_products_security_response09186a008070c75a.html
	http://www.microsoft.com/technet/security/bulletin/ms06-040.mspx
CVE:	CVE-2006-3439

INFORMATION BULLETIN

Q-270: Vulnerability in Server Service

[Microsoft Security Bulletin MS06-040 (921883)]

Microsoft Security Bulletin MS06-040

Vulnerability in Server Service Could Allow Remote Code Execution (921883)

Summary

General Information

Executive Summary

Frequently Asked Questions (FAQ) Related to This Security Update

Vulnerability Details

Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

Mitigating Factors for Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

Workarounds for Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

FAQ for Buffer Overrun in Server Service Vulnerability - CVE-2006-3439:

Security Update Information

Windows Server 2003 (all versions)

Windows XP (all versions)

Windows 2000 (all versions)

•	Microsoft Windows 2000 Service Pack 4 — Download the update
•	Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2 — Download the update
•	Microsoft Windows XP Professional x64 Edition — Download the update
•	Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1 — Download the update
•	Microsoft Windows Server 2003 for Itanium-based Systems and Microsoft Windows Server 2003 with SP1 for Itanium-based Systems — Download the update
•	Microsoft Windows Server 2003 x64 Edition — Download the update

•	US-CERT for working with us on Buffer Overrun in Server Service Vulnerability (CVE-2006-3439).
•	SANS for working with us on Buffer Overrun in Server Service Vulnerability (CVE-2006-3439).

•	Security updates are available at 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 Microsoft Update Web site.

•	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.

•	The Microsoft TechNet Security Web site provides additional information about security in Microsoft products.
•	TechNet Update Management Center
•	Microsoft Software Update Services
•	Microsoft Windows Server Update Services
•	Microsoft Baseline Security Analyzer (MBSA)
•	Windows Update
•	Microsoft Update
•	Windows Update Catalog: For more information about the Windows Update Catalog, see Microsoft Knowledge Base Article 323166.
•	Office Update