•	An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•	In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.
•	The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
•	Users who have installed and are using the Office Document Open Confirmation Tool for Office 2000 will be prompted with Open, Save, or Cancel before opening a document. The features of the Office Document Open Confirmation Tool are incorporated in Office XP and Office 2003.

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.

Do not open or save Microsoft Word files that you receive from untrusted sources or that you received unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a file.

What is the scope of the vulnerability?
A remote code execution vulnerability exists in Word. An attacker could exploit this vulnerability when Word parses a file that contains a malformed string.

If a user were logged on with administrative user rights, 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. Users whose accounts are configured to have fewer user rights on the system could be less affected than users who operate with administrative user rights.

What causes the vulnerability?
When Microsoft Word opens a specially crafted Word file, it may corrupt system memory in such a way that an attacker could execute arbitrary code.

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

How could an attacker exploit the vulnerability?
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially-crafted file to the user and by persuading the user to open the file.

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.

What systems are primarily at risk from the vulnerability?
Workstations and terminal servers are primarily at risk. Servers could be at more risk if users who have sufficient administrative permissions are given the ability to log on to servers and to run programs. However, best practices strongly discourage allowing this.

What does the update do?
The update removes the vulnerability by modifying the way that Microsoft Word parses the file and validates the string 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. This security bulletin addresses the privately disclosed vulnerability as well as additional issues discovered through internal investigations.

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.

•	An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•	In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.
•	The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
•	Users who have installed and are using the Office Document Open Confirmation Tool for Office 2000 will be prompted with Open, Save, or Cancel before opening a document. The features of the Office Document Open Confirmation Tool are incorporated in Office XP and Office 2003.

Do not open or save Microsoft Word files that you receive from untrusted sources or that you received unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a file.

What is the scope of the vulnerability?
A remote code execution vulnerability exists in Microsoft Word, and could be exploited when Word opens a specially crafted mail merge file. Such a specially crafted file might be included as an e-mail attachment or hosted on a malicious web site. Viewing or previewing a malformed e-mail message in an affected version of Outlook could not lead to exploitation of this vulnerability. An attacker could exploit the vulnerability by constructing a specially crafted Word file that could allow remote code execution.

If a user were logged on with administrative user rights, 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. Users whose accounts are configured to have fewer user rights on the system could be less affected than users who operate with administrative user rights.

What causes the vulnerability?
When Microsoft Word opens a specially crafted Word mail merge file, it may corrupt system memory in such a way that an attacker could execute arbitrary code.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause arbitrary code to run with the privileges of the user who opened the file.

How could an attacker exploit the vulnerability?
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially-crafted file to the user and by persuading the user to open the file.

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.

What systems are primarily at risk from the vulnerability?
Workstations and terminal servers are primarily at risk. Servers could be at more risk if users who have sufficient administrative permissions are given the ability to log on to servers and to run programs. However, best practices strongly discourage allowing this.

What does the update do?
The update removes the vulnerability by modifying the way that Microsoft Word parses the length of a mail merge record 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. This security bulletin addresses the privately disclosed vulnerability as well as additional issues discovered through internal investigations.

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.

•	An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•	In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.
•	The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.
•	Users who have installed and are using the Office Document Open Confirmation Tool for Office 2000 will be prompted with Open, Save, or Cancel before opening a document. The features of the Office Document Open Confirmation Tool are incorporated in Office XP and Office 2003.

Do not open or save Microsoft Word files that you receive from untrusted sources or that you received unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a file.

What is the scope of the vulnerability?
A remote code execution vulnerability exists in Microsoft Word, and could be exploited when Word opens a specially crafted file. Such a specially crafted file might be included as an e-mail attachment or hosted on a malicious web site. Viewing or previewing a malformed e-mail message in an affected version of Outlook could not lead to exploitation of this vulnerability. An attacker could exploit the vulnerability by constructing a specially crafted Word file that could allow remote code execution.

If a user were logged on with administrative user rights, 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. Users whose accounts are configured to have fewer user rights on the system could be less affected than users who operate with administrative user rights.

What causes the vulnerability?
When Microsoft Word opens a specially crafted Word file, it may corrupt system memory in such a way that an attacker could execute arbitrary code.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause arbitrary code to run with the privileges of the user who opened the file.

How could an attacker exploit the vulnerability?
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially-crafted file to the user and by persuading the user to open the file.

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.

What systems are primarily at risk from the vulnerability?
Workstations and terminal servers are primarily at risk. Servers could be at more risk if users who have sufficient administrative permissions are given the ability to log on to servers and to run programs. However, best practices strongly discourage allowing this.

What does the update do?
The update removes the vulnerability by modifying the way that Microsoft Word parses the length of a record before it passes the message to the allocated buffer.

When this security bulletin was issued, had this vulnerability been publicly disclosed?
Yes. This vulnerability has been publicly disclosed. It has been assigned Common Vulnerability and Exposure number CVE-2006-4534.

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-2006-4534.

•	An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
•	In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.
•	The vulnerability cannot be exploited automatically through e-mail. For an attack to be successful a user must open an attachment that is sent in an e-mail message.

Do not open or save Microsoft Word files that you receive from untrusted sources or that you received unexpectedly from trusted sources. This vulnerability could be exploited when a user opens a file.

What is the scope of the vulnerability?
A remote code execution vulnerability exists in Word for Mac. An attacker could exploit this vulnerability when Word for Mac parses a file that contains a malformed string.

If a user were logged on with administrative user rights, 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. Users whose accounts are configured to have fewer user rights on the system could be less affected than users who operate with administrative user rights.

What causes the vulnerability?
When Microsoft Word for Mac opens a specially crafted Word file, it may corrupt system memory in such a way that an attacker could execute arbitrary code.

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

How could an attacker exploit the vulnerability?
In an e-mail attack scenario, an attacker could exploit the vulnerability by sending a specially-crafted file to the user and by persuading the user to open the file.

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Word file that is used to attempt to exploit this vulnerability. In addition, compromised Web sites and Web sites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's site.

What systems are primarily at risk from the vulnerability?
Workstations are primarily at risk. Servers could be at more risk if users who have sufficient administrative permissions are given the ability to log on to servers and to run programs. However, best practices strongly discourage allowing this.

What does the update do?
The update removes the vulnerability by modifying the way that Microsoft Word for Mac parses the file and validates the string.

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. This security bulletin addresses the privately disclosed vulnerability as well as additional issues discovered through internal investigations.

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.

Important Before you install this update, make sure that the following requirements have been met:

•	Microsoft Windows Installer 2.0 must be installed. Microsoft Windows Server 2003, Windows XP and Microsoft Windows 2000 Service Pack 3 (SP3) include Windows Installer 2.0 or a later version. To install the latest version of Windows Installer, visit one of the following Microsoft Web sites:

Windows Installer 2.0 for Windows 95, Windows 98, Windows 98 SE, and Windows Millennium Edition

Windows Installer 2.0 for Windows 2000 and Windows NT 4.0

•	Office 2000 Service Pack 3 (SP3) must be installed. Before you install this update, install Office 2000 SP3. For more information about how to install Office 2000 SP3, see Microsoft Knowledge Base Article 326585.

For more information about how to determine the version of Office 2000 that is installed on your computer, see Microsoft Knowledge Base Article 255275.

Inclusion in Future Service Packs

None. Service Pack 3 is the last service pack for Office 2000.

Restart Requirement

To help reduce the chance that a restart will be required, stop all affected services and close all applications that may use the affected files prior to installing the security update. For more information about the reasons why you may be prompted to restart, see Microsoft Knowledge Base Article 887012.

Removal Information

After you install the update, you cannot remove it. To revert to an installation before the update was installed; you must remove the application, and then install it again from the original CD-ROM.

Office Update Web Site

We recommend that you install the Microsoft Office 2000 client updates by using the Office Update Web site. The Office Update Web site detects which installation you have and prompts you to install exactly what you must have to make sure that your installation is completely up to date.

To have the Office Update Web site detect the updates that you must install on your computer, visit the Office Update Web site, and then click Check for Updates. After detection is complete, you will receive a list of recommended updates for your approval. Click Agree and Install to complete the process.

For detailed information about how to manually install this update, review the following section.

Installation Information

The security update supports the following setup switches.

Supported Security Update Installation Switches
Switch	Description
/q	Specifies quiet mode, or suppresses prompts, when files are being extracted.
/q:u	Specifies user-quiet mode, which presents some dialog boxes to the user.
/q:a	Specifies administrator-quiet mode, which does not present any dialog boxes to the user.
/t:path	Specifies the target folder for extracting files.
/c	Extracts the files without installing them. If /t:path is not specified, you are prompted for a target folder.
/c:path	Overrides the install command that is defined by author. Specifies the path and name of the Setup.inf or .exe file.
/r:n	Never restarts the computer after installation.
/r:I	Prompts the user to restart the computer if a restart is required, except when used with /q:a.
/r:a	Always restarts the computer after installation.
/r:s	Restarts the computer after installation without prompting the user.
/n:v	No version checking - Install the program over any earlier version.

Note These switches do not necessarily work with all updates. If a switch is not available, that functionality is required for the correct installation of the update. Also, using the /n:v switch is unsupported and may result in an unbootable system. If the installation is unsuccessful, you should contact your support professional to understand why it could not install.

For more information about the supported setup switches, see Microsoft Knowledge Base Article 197147.

Note The full file office update is intended for both client and administrative deployment scenarios.

Client Deployment Information

1.	Download this security update for Word 2000.
2.	Click Save this program to disk, and then click OK.
3.	Click Save.
4.	Using Windows Explorer, find the folder that contains the saved file, and then double-click the saved file.
5.	If you are prompted to install the update, click Yes.
6.	Click Yes to accept the License Agreement.
7.	Insert your original source CD-ROM when you are prompted to do so, and then click OK.
8.	When you receive a message that states the installation was successful, click OK.

Note If the security update is already installed on your computer, you receive the following error message: This update has already been applied or is included in an update that has already been applied.

Client Installation File Information

The English version of this 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.

Word 2000:

File Name	Version	Date	Time	Size
Winword.exe	9.0.0.8951	08-Sep-2006	18:53	8,831,028

Verifying that the Update Has Been Applied

•	Microsoft Baseline Security Analyzer

Note MBSA 1.2.1 uses an integrated version of the Office Detection Tool (ODT) which does not support remote scans of this issue. For more information about MBSA, visit the MBSA Web site. For more information about MBSA support, visit the following Microsoft Baseline Security Analyzer 1.2 Q&A 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.

If you installed your application from a server location, the server administrator must update the server location with the administrative update and deploy that update to your computer.

Installation Information

The following setup switches are relevant to administrative installations as they allow an administrator to customize how the files are extracted from the security update.

Supported Security Update Installation Switches
Switch	Description
/?	Displays the command-line options.
/q	Specifies quiet mode, or suppresses prompts, when files are being extracted.
/t:path	Specifies the target folder for extracting files.
/c	Extracts the files without installing them. If /t:path is not specified, you are prompted for a target folder.
/c:path	Overrides the install command that is defined by author. Specifies the path and name of the Setup.inf or .exe file.

For more information about the supported setup switches, see Microsoft Knowledge Base Article 197147.

Administrative Deployment Information

To update your administrative installation, follow these steps:

1.	Download this security update for Word 2000.
2.	Click Save this program to disk, and then click OK.
3.	Click Save.
4.	Using Windows Explorer, locate the folder that contains the saved file. Click Start, click Run, type the following command, and then click OK to extract the .msp file: [path\name of EXE file] /c /t:C:\AdminUpdate Note Double-clicking the .exe file does not extract the .msp file; it applies the update to the local computer. In order to update an administrative image, you must first extract the .msp file.
5.	Click Yes to accept the License Agreement.
6.	Click Yes if you are prompted to create the folder.
7.	If you are familiar with the procedure for updating your administrative installation, click Start, click Run, type the following command, and then click OK: msiexec /a Admin Path\MSI File /p C:\AdminUpdate\MSP File SHORTFILENAMES=TRUE Note Admin Path is the path of your administrative installation point for your application (for example, C:\Office2000), MSI File is the .msi database package for the application (for example, Data1.msi), and MSP File is the name of the administrative update (for example, SHAREDff.msp). Note You can append /qb+ to the command line so that the Administrative Installation dialog box and the End User License Agreement dialog box do not appear.
8.	Click Next in the provided dialog box. Do not change your CD key, installation location, or company name in the provided dialog box.
9.	Click I accept the terms in the License Agreement, and then click Install.

At this point, your administrative installation point is updated. Next, you must update the workstations configurations that were originally installed from this administrative installation. To do this, please review the “Workstation Deployment Information” section. Any new installations that you run from this administrative installation point will include the update.

Warning Any workstation configuration that was originally installed from this administrative installation before you installed the update cannot use this administrative installation for actions like repairing Office or adding new features until you complete the steps in the “Workstation Deployment Information” section for this workstation.

Workstation Deployment Information

To deploy the update to the client workstations, click Start, click Run, type the following command, and then click OK:

msiexec /I Admin Path\MSI File /qb REINSTALL=Feature List REINSTALLMODE=vomu

Note Admin Path is the path of your administrative installation point for your application (for example, C:\Office2000), MSI File is the .msi database package for the application (for example, Data1.msi), and Feature List is the list of feature names (case sensitive) that must be reinstalled for the update.

To install all features, you can use REINSTALL=ALL or you can install the following features.

Product	Feature
O9PRM, O9PRO, O9SBE, O9PIPC1, O9PIPC2, O9STD, O9WDI, O9WRD	WORDFiles

Note Administrators working in managed environments can find complete resources for deploying Office updates in an organization at the Office Admin Update Center. At that site, scroll down and look under the Update Resources section for the software version you are updating. The Windows Installer Documentation also provides more information about the parameters supported by Windows Installer.

Administrative Installation File Information

The English version of this 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.

Word 2000:

File Name	Version	Date	Time	Size
Winword.exe	9.0.0.8951	08-Sep-2006	18:53	8,831,028

Verifying that the Update Has Been Applied

•	Microsoft Baseline Security Analyzer

Note MBSA 1.2.1 uses an integrated version of the Office Detection Tool (ODT) which does not support remote scans of this security update. For more information about MBSA, visit the MBSA 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.

Important: Before you install this