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HistoryOct 11, 2006 - 12:00 a.m.

Microsoft Security Bulletin MS06-061 Vulnerabilities in Microsoft XML Core Services Could Allow Remote Code Execution (924191)

2006-10-1100:00:00
vulners.com
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Microsoft Security Bulletin MS06-061
Vulnerabilities in Microsoft XML Core Services Could Allow Remote Code Execution (924191)

Version: 1.0
Summary

Who Should Read this Document: Customers who use Microsoft Windows or Microsoft Office

Impact of Vulnerability: Remote Code Execution

Maximum Severity Rating: Critical

Recommendation: Customers should apply the update immediately

Security Update Replacement: This bulletin replaces a prior security update. See the frequently asked questions (FAQ) section of this bulletin for the complete list

Caveats: None

Tested Software and Security Update Download Locations:

Affected Software:

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Windows 2000 Service Pack 4 - Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows XP Service Pack 1 - Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows XP Service Pack 2 – Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows XP Professional x64 Edition – Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows Server 2003 - Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows Server 2003 Service Pack 1 – Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows Server 2003 for Itanium-based Systems and Microsoft Windows Server 2003 with SP1 for Itanium-based Systems – Download the update (KB924191)

Microsoft XML Parser 2.6 (all versions) and Microsoft XML Core Services 3.0 (all versions) on Microsoft Windows Server 2003 x64 Edition – Download the update (KB924191)

Microsoft Office 2003 Service Pack 1 or Service Pack 2 with Microsoft XML Core Services 5.0 Service Pack 1 - Download the update (KB924424)

Non-Affected Software:

Windows 2000 Service Pack 4 running Microsoft XML Core Services 2.5

Microsoft Windows XP Service Pack 1 running Microsoft XML Core Services 2.5

Microsoft Windows XP Service Pack 2 running Microsoft XML Core Services 2.5

Microsoft Windows Server 2003 running Microsoft XML Core Services 2.5

Microsoft Windows Server 2003 Service Pack 1 running Microsoft XML Core Services 2.5

Tested Microsoft Windows Components:

Affected Components:

Microsoft XML Core Services 4.0 when installed on Windows 2000 Service Pack 4 – Download the update (KB925672)

Microsoft XML Core Services 4.0 when installed on Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2 – Download the update (KB925672)

Microsoft XML Core Services 4.0 when installed on Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1 – Download the update (KB925672)

Microsoft XML Core Services 6.0 when installed on Windows 2000 Service Pack 4 – Download the update (KB925673)

Microsoft XML Core Services 6.0 when installed on Microsoft Windows XP Service Pack 1 and Microsoft Windows XP Service Pack 2 – Download the update (KB925673)

Microsoft XML Core Services 6.0 when installed on Microsoft Windows Server 2003 and Microsoft Windows Server 2003 Service Pack 1 – Download the update (KB925673)

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.

Note The security updates for Microsoft Windows Server 2003, Windows Server 2003 Service Pack 1, and Windows Server 2003 x64 Edition also apply to Windows Server 2003 R2.
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General Information

Executive Summary

Executive Summary:

This update resolves two newly discovered, privately reported vulnerabilities. Each vulnerability is documented in its own subsection in the "Vulnerability Details" section of this bulletin.

If a user is 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 impacted than users who operate with administrative user rights.

We recommend that customers apply the update immediately.

Severity Ratings and Vulnerability Identifiers:
Vulnerability Identifiers Impact of Vulnerability Windows 2000 Service Pack 4 Windows XP Service Pack 1 Windows XP Service Pack 2 Windows Server 2003 Windows Server 2003 Service Pack 1 Microsoft Office 2003 Service Pack 1 or Service Pack 2 Microsoft XML Core Services 4.0 Microsoft XML Core Services 6.0

Microsoft XML Core Services Vulnerability - CVE-2006-4685

Information Disclosure

Important

Important

Important

Low

Low

Important

Important

Important

XSLT Buffer Overrun Vulnerability - CVE-2006-4686

Remote Code Execution

Critical

Critical

Critical

Critical

Critical

Critical

Critical

Critical

Aggregate Severity of All Vulnerabilities

Critical

Critical

Critical

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

The Microsoft Windows XP Professional x64 Edition severity rating is the same as the Windows XP Service Pack 2 severity rating.

The Microsoft Windows Server 2003 R2 Systems severity rating is the same as the Windows Server 2003 severity rating.

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

The Microsoft Windows Server 2003 with SP1 for Itanium-based Systems severity rating is the same as the Windows Server 2003 Service Pack 1 severity rating.

The Microsoft Windows Server 2003 x64 Edition severity rating is the same as the Windows Server 2003 Service Pack 1 severity rating.

The Microsoft Office 2003 Service Pack 1 or Service Pack 2 severity rating is the same as the Windows operating system version that they resides on.

The Microsoft XML Core Services 4.0 severity rating is the same as the Windows operating system version that it resides on.

The Microsoft XML Core Services 6.0 severity rating is the same as the Windows operating system version that it resides on.
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Frequently Asked Questions (FAQ) Related to This Security Update

Why does this update address several reported security vulnerabilities?
This update contains support for several vulnerabilities because the modifications that are required to address these issues are located in related files. Instead of having to install several updates that are almost the same, customers can install only this update.

What version of Microsoft XML Core Services is installed on my system?
For information about the different Microsoft XML Core Services versions that are available and the products that install them, see Microsoft Knowledge Base Article 269238.

Does this update contain any security-related changes to functionality?
Yes. Besides the changes that are listed in the "Vulnerability Details" section of this bulletin, this update sets a kill bit for a list of Class Identifiers (CLSIDs) for Microsoft XML Core Services 2.6.

The CLSIDs and corresponding files where the Microsoft XML Core Services 2.6 functionality is contained are as follows.

Class Identifier

File

f5078f22-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f1b-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f1c-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f1d-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f1e-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f21-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f1f-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f20-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f28-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f29-c551-11d3-89b9-0000f81fe221

Msxml2.dll

f5078f26-c551-11d3-89b9-0000f81fe221

Msxml2.dll

What updates does this release replace?
This security update replaces a prior security update. The security bulletin ID and affected operating systems are listed in the following table.
Bulletin ID Windows 2000 Service Pack 4 Windows XP Service Pack 1 Windows XP Service Pack 2 Windows Server 2003 Windows Server 2003 Service Pack 1 Microsoft Office 2003 Service Pack 1 or Service Pack 2 Microsoft XML Core Services 4.0 Microsoft XML Core Services 6.0

MS02-008

Replaced

Replaced

Replaced

Replaced

Replaced

Not Applicable

Replaced

Not Applicable

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 followingMicrosoft 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.

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

Microsoft Office 2003 Service Pack 1 or Service Pack 2

Yes

Yes

Microsoft XML Core Services 4.0

Yes

Yes

Microsoft XML Core Services 6.0

Yes

Yes

Note MBSA 1.2.1 uses an integrated version of the Office Detection Tool (ODT) for Microsoft Office 2003 Service Pack 1 or Service Pack 2 with Microsoft XML Core Services 5.0 Service Pack 1, which does not support remote scans for this security update. For more information about MBSA, visit the MBSA Web site.

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.

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

Microsoft Office 2003 Service Pack 1 or Service Pack 2

Yes

Yes

Microsoft XML Core Services 4.0

Yes

Yes

Microsoft XML Core Services 6.0

Yes

Yes

SMS 2.0 and SMS 2003 Software Update Services (SUS) Feature Pack can use MBSA 1.2.1 for detection and therefore have the same limitation that is listed earlier in this bulletin related to programs that MBSA 1.2.1 does not detect.

For SMS 2.0, the SMS SUS Feature Pack, which includes the Security Update Inventory Tool (SUIT), can be used by SMS to detect security updates. SMS SUIT uses the MBSA 1.2.1 engine for detection. For more information about SUIT, visit the following Microsoft Web site. For more information about the limitations of SUIT, see Microsoft Knowledge Base Article 306460. The SMS SUS Feature Pack also includes the Microsoft Office Inventory Tool to detect required updates for Microsoft Office applications.

For SMS 2003, the SMS 2003 Inventory Tool for Microsoft Updates (ITMU) can be used by SMS to detect security updates that are offered by Microsoft Update and that are supported by Windows Server Update Services. For more information about the SMS 2003 ITMU, visit the following Microsoft Web site. SMS 2003 can also use the Microsoft Office Inventory Tool to detect required updates for Microsoft Office applications.

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

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

Microsoft XML Core Services Vulnerability - CVE-2006-4685:

A vulnerability exists in Microsoft XML Core Services that could allow for information disclosure because the XMLHTTP ActiveX control incorrectly interprets an HTTP server-side redirect. An attacker could exploit the vulnerability by constructing a specially crafted Web page that could potentially lead to information disclosure if a user visited that page or clicked a link in a specially crafted e-mail message. An attacker who successfully exploited this vulnerability could access content from another domain retrieved using the credentials of the user browsing the Web at the client. In addition, compromised Web sites and Web sites that accept or host user-provided content or advertisements could contain specially crafted content that could exploit this vulnerability. However, user interaction is required to exploit this vulnerability.

Mitigating Factors for Microsoft XML Core Services Vulnerability - CVE-2006-4685:

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Web page that is used to exploit this vulnerability. An attacker would have no way to force users to visit the page. Instead, an attacker would have to persuade users to visit the Web site, typically by getting them to click a link in an e-mail message or instant messenger message that takes users to the attacker's Web site.

By default, Internet Explorer on Windows Server 2003 runs in a restricted mode that is known as Enhanced Security Configuration. This mode mitigates this vulnerability from sites that are not explicitly allowed to run script and ActiveX controls. See the FAQ section of this security update for more information about Internet Explorer Enhanced Security Configuration.
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Workarounds for Microsoft XML Core Services Vulnerability - CVE-2006-4685:

Set Internet and Local intranet security zone settings to “High” to prompt before running ActiveX controls and active scripting in the Internet zone and in the Local intranet zone.

You can help protect against this vulnerability by changing your settings for the Internet security zone to prompt before running ActiveX controls and active scripting. You can do this by setting your browser security to High.

To raise the browsing security level in Microsoft Internet Explorer:

On the Internet Explorer Tools menu, click Internet Options.

In the Internet Options dialog box, click the Security tab, and then click the Internet icon.

Under Security level for this zone, move the slider to High. This sets the security level for all Web sites you visit to High.

Note If no slider is visible, click Default Level, and then move the slider to High.

Note Setting the level to High may cause some Web sites to work incorrectly. If you have difficulty using a Web site after you change this setting, and you are sure the site is safe to use, you can add that site to your list of trusted sites. This will allow the site to work correctly even with the high security setting.

Alternatively, you can change you settings to prompt before running ActiveX controls only by following these steps:

In Internet Explorer, click Internet Options on the Tools menu.

Click the Security tab.

Click Internet, and then click Custom Level.

Under Settings, in the ActiveX controls and plug-ins section, under Run ActiveX controls and plug-ins, click Prompt.

In the Scripting section, under Active Scripting, click Prompt, and then click OK.

Click Local intranet, and then click Custom Level.

Under Settings, in the ActiveX controls and plug-ins section, under Run ActiveX controls and plug-ins, click Prompt.

In the Scripting section, under Active Scripting, click Prompt.

Click OK two times to return to Internet Explorer.

Impact of Workaround: There are side effects to prompting before running ActiveX controls. Many Web sites that are on the Internet or on an intranet use ActiveX to provide additional functionality. For example, an online e-commerce site or banking site may use ActiveX controls to provide menus, ordering forms, or even account statements. Prompting before running ActiveX controls is a global setting that affects all Internet and intranet sites. You will be prompted frequently when you enable this workaround. For each prompt, if you feel you trust the site that you are visiting, click Yes to run ActiveX controls. If you do not want to be prompted for all these sites, use the "Restrict Web sites to only your trusted Web sites" workaround.
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FAQ for Microsoft XML Core Services Vulnerability - CVE-2006-4685:

What is the scope of the vulnerability?
This is an information disclosure vulnerability. An attacker could exploit the vulnerability by constructing a specially crafted Web page that could potentially lead to information disclosure if a user visited that page or clicked a link in a specially crafted e-mail message. An attacker who successfully exploited this vulnerability could access content from another domain retrieved using the credentials of the user browsing the Web at the client. However, user interaction is required to exploit this vulnerability.

What causes the vulnerability?
A flaw exists in how the XMLHTTP control applies IE security settings to a redirected data stream returned in response to a request for data from a Web site.

What is Microsoft XML Core Services (MSXML)?
Microsoft XML Core Services (MSXML) allows customers who use JScript, Visual Basic Scripting Edition (VBScript), and Microsoft Visual Studio 6.0 to build high-performance XML-based applications that provide a high degree of interoperability with other applications that adhere to the XML 1.0 standard. See the MSDN Web site for more information regarding MSXML.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could read cookies or other data from another security zone or domain in Internet Explorer.

Who could exploit the vulnerability?
An attacker could host a specially crafted Web site that is designed to exploit this vulnerability through Internet Explorer and then persuade a user to view the Web site. This can also include Web sites that accept user-provided content or advertisements, Web sites that host user-provided content or advertisements, and compromised Web sites. These Web sites could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to persuade users to visit the Web site, typically by getting them to click a link in an e-mail message or in an Instant Messenger request that takes users to the attacker's Web site. It could also be possible to display specially crafted Web content by using banner advertisements or by using other methods to deliver Web content to affected systems.

What systems are primarily at risk from the vulnerability?
This vulnerability requires that a user is logged on and visits a Web site for any malicious action to occur. Therefore, any systems where Internet Explorer is used frequently, such as workstations or terminal servers, are at the most risk from this vulnerability. Systems that are not typically used to visit Web sites, such as most server systems, are at a reduced risk.

What is the Internet Explorer Enhanced Security Configuration?
Internet Explorer Enhanced Security Configuration is a group of preconfigured Internet Explorer settings that reduce the likelihood of a user or of an administrator downloading and running specially crafted Web content on a server. Internet Explorer Enhanced Security Configuration reduces this risk by modifying many security-related settings. This includes the settings on the Security tab and the Advanced tab in the Internet Options dialog box. Some of the important modifications include the following:

Security level for the Internet zone is set to High. This setting disables scripts, ActiveX controls, Microsoft Java Virtual Machine (MSJVM), and file downloads.

Automatic detection of intranet sites is disabled. This setting assigns all intranet Web sites and all Universal Naming Convention (UNC) paths that are not explicitly listed in the Local intranet zone to the Internet zone.

Install On Demand and non-Microsoft browser extensions are disabled. This setting prevents Web pages from automatically installing components and prevents non-Microsoft extensions from running.

Multimedia content is disabled. This setting prevents music, animations, and video clips from running.

For more information regarding Internet Explorer Enhanced Security Configuration, see the guide, Managing Internet Explorer Enhanced Security Configuration, at the following Web site.

What does the update do?
The update removes the vulnerability by correcting the behavior of XML Core Services. XML Core Services will now interpret a server-side redirect in the XMLHTTP control differently and abort properly in previously unhandled circumstances.

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.
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XSLT Buffer Overrun Vulnerability - CVE-2006-4686:

A vulnerability exists in XSLT processing that could allow remote code execution on an affected system. An attacker could exploit the vulnerability by constructing a malicious Web page that could potentially allow remote code execution if a user visited that page. An attacker who successfully exploited this vulnerability could take complete control of an affected system.

Mitigating Factors for XSLT Buffer Overrun Vulnerability - CVE-2006-4686:

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Web page that is used to exploit this vulnerability. An attacker would have no way to force users to visit that page. Instead, an attacker would have to persuade users to visit the Web site, typically by getting them to click a link in an e-mail message or instant messenger message that takes users to the attacker's Web site.

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.
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Workarounds for XSLT Buffer Overrun Vulnerability - CVE-2006-4686:

We have not identified any workarounds for this vulnerability.
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FAQ for XSLT Buffer Overrun Vulnerability - CVE-2006-4686:

What is the scope of the vulnerability?
This is a vulnerability that could allow remote code execution. An attacker could exploit the vulnerability by constructing a specially crafted Web page that could potentially lead to remote code execution if a user visited that page or clicked a link in a specially crafted e-mail message. If a user is 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 impacted than users who operate with administrative user rights.

What causes the vulnerability?
A vulnerability in a string buffer, within the XSLT control within MSXML.

What is XSLT?
Extensible Stylesheet Language Transformations (XSLT) is used to manipulate XML data or extract content that needs to be reused.

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?
An attacker could host a specially crafted Web site that is designed to exploit this vulnerability through Internet Explorer and then persuade a user to view the Web site. This can also include Web sites that accept user-provided content or advertisements, Web sites that host user-provided content or advertisements, and compromised Web sites. These Web sites could contain specially crafted content that could exploit this vulnerability. In all cases, however, an attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to persuade users to visit the Web site, typically by getting them to click a link in an e-mail message or in an Instant Messenger request that takes users to the attacker's Web site. It could also be possible to display specially crafted Web content by using banner advertisements or by using other methods to deliver Web content to affected systems.

What systems are primarily at risk from the vulnerability?
This vulnerability requires that a user is logged on and visits a Web site for any malicious action to occur. Therefore, any systems where Internet Explorer is used frequently, such as workstations or terminal servers, are at the most risk from this vulnerability. Systems that are not typically used to visit Web sites, such as most server systems, are at a reduced risk.

What is the Internet Explorer Enhanced Security Configuration?
Internet Explorer Enhanced Security Configuration is a group of preconfigured Internet Explorer settings that reduce the likelihood of a user or of an administrator downloading and running specially crafted Web content on a server. Internet Explorer Enhanced Security Configuration reduces this risk by modifying many security-related settings. This includes the settings on the Security tab and the Advanced tab in the Internet Options dialog box. Some of the important modifications include the following:

Security level for the Internet zone is set to High. This setting disables scripts, ActiveX controls, Microsoft Java Virtual Machine (MSJVM), and file downloads.

Automatic detection of intranet sites is disabled. This setting assigns all intranet Web sites and all Universal Naming Convention (UNC) paths that are not explicitly listed in the Local intranet zone to the Internet zone.

Install On Demand and non-Microsoft browser extensions are disabled. This setting prevents Web pages from automatically installing components and prevents non-Microsoft extensions from running.

Multimedia content is disabled. This setting prevents music, animations, and video clips from running.

For more information regarding Internet Explorer Enhanced Security Configuration, see the guide, Managing Internet Explorer Enhanced Security Configuration, at the following Web site.

What does the update do?
The update removes the vulnerability by correcting the issue within the affected string 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.

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 (October 10, 2006): Bulletin published.

Related for SECURITYVULNS:DOC:14614