Microsoft Security Bulletin MS08-060 - Critical

Vulnerability in Active Directory Could Allow Remote Code Execution (957280)

Published: Tuesday, October 14, 2008 | Updated: Wednesday, October 15, 2008

Version: 1.1

General Information

Executive Summary

This security update resolves a privately reported vulnerability in implementations of Active Directory on Microsoft Windows 2000 Server. The vulnerability could allow remote code execution if an attacker gains access to an affected network. This vulnerability only affects Microsoft Windows 2000 servers configured to be domain controllers. If a Microsoft Windows 2000 server has not been promoted to a domain controller, it will not be listening to Lightweight Directory Access Protocol (LDAP) or LDAP over SSL (LDAPS) queries, and will not be exposed to this vulnerability.

This security update is rated Critical for implementations of Active Directory on Microsoft Windows 2000 Server. For more information, see the subsection, Affected and Non-Affected Software, in this section.

The security update addresses the vulnerability by correctly allocating memory for client LDAP requests. For more information about the vulnerability, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.

Recommendation. Microsoft recommends that customers apply the update immediately.

Known Issues. None

Affected and Non-Affected Software

The following software have been tested to determine which versions or editions are affected. Other versions or editions are either past their support life cycle or are not affected. To determine the support life cycle for your software version or edition, visit Microsoft Support Lifecycle.

Affected Software

Operating System	Component	Maximum Security Impact	Aggregate Severity Rating	Bulletins Replaced by this Update
Microsoft Windows 2000 Server Service Pack 4	Active Directory	Remote Code Execution	Critical	MS08-035

Non-Affected Software

Operating System	Component
Microsoft Windows 2000 Professional Service Pack 4	Not applicable
Windows XP Service Pack 2 and Windows XP Service Pack 3	ADAM
Windows XP Professional x64 Edition and Windows XP Professional x64 Edition Service Pack 2	ADAM
Windows Server 2003 Service Pack 1 and Windows Server 2003 Service Pack 2	Active Directory ADAM
Windows Server 2003 x64 Edition and Windows Server 2003 x64 Edition Service Pack 2	Active Directory ADAM
Windows Server 2003 with SP1 for Itanium-based Systems and Windows Server 2003 with SP2 for Itanium-based Systems	Active Directory
Windows Vista and Windows Vista Service Pack 1	Not applicable
Windows Vista x64 Edition and Windows Vista x64 Edition Service Pack 1	Not applicable
Windows Server 2008 for 32-bit Systems	Active Directory AD LDS
Windows Server 2008 for x64-based Systems	Active Directory AD LDS
Windows Server 2008 for Itanium-based Systems	Not applicable

Frequently Asked Questions (FAQ) Related to This Security Update

Where are the file information details?
The file information details can be found in Microsoft Knowledge Base Article 957280.

I am running one of the platforms that are listed in the affected software table. Why am I not being offered the update?
The update will only be offered to systems on which the affected component is both installed and enabled. Microsoft Windows 2000 Server systems not configured in the role of a domain controller are not affected and will not receive this update.

Does this issue also affect Active Directory Application Mode (ADAM) or Active Directory Lightweight Directory Service (AD LDS)?
No. This issue only affects Microsoft Windows 2000 servers configured as Active Directory domain controllers. No other platforms or services are affected.

I am using an older release of the software discussed in this security bulletin. What should I do?
The affected software listed in this bulletin have been tested to determine which releases are affected. Other releases are past their support life cycle. To determine the support life cycle for your software release, visit Microsoft Support Lifecycle.

It should be a priority for customers who have older releases of the software to migrate to supported releases to prevent potential exposure to vulnerabilities. For more information about the Windows Product Lifecycle, visit Microsoft Support Lifecycle. For more information about the extended security update support period for these software versions or editions, visit Microsoft Product Support Services.

Customers who require custom support for older releases 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 Microsoft Worldwide Information, 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.

Vulnerability Information

Severity Ratings and Vulnerability Identifiers

Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software	Active Directory Overflow Vulnerability - CVE-2008-4023	Aggregate Severity Rating
Active Directory on Microsoft Windows 2000 Server Service Pack 4	Critical Remote Code Execution	Critical

Active Directory Overflow Vulnerability - CVE-2008-4023

A remote code execution vulnerability exists in implementations of Active Directory on Microsoft Windows 2000 Server. The vulnerability is due to incorrect memory allocation when receiving specially crafted LDAP or LDAPS requests. An attacker who successfully exploited this vulnerability could take complete control of an affected system.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2008-4023.

Mitigating Factors for Active Directory Overflow Vulnerability - CVE-2008-4023

Workarounds for Active Directory Overflow Vulnerability - CVE-2008-4023

FAQ for Active Directory Overflow Vulnerability - CVE-2008-4023

What is the scope of the vulnerability?
This is a remote code execution vulnerability. An attacker who successfully exploited this vulnerability could take complete control of an affected system remotely. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

Note. Attacks attempting to exploit this vulnerability could also result in a denial of service condition. An attacker could also exploit this vulnerability to force the system to restart. However, since remote code execution is possible, the aggregate scope is larger than only a denial of service.

What causes the vulnerability?
The LDAP service incorrectly allocates memory for specially crafted LDAP requests.

What is Active Directory?
The main purpose of Active Directory is to provide central authentication and authorization services for Windows-based computers.

What is LDAP?
Lightweight Directory Access Protocol (LDAP) is an open network protocol standard designed to provide access to distributed directories.

What is LDAP over SSL?
By default, LDAP traffic is transmitted unsecured. However, it is possible to make LDAP traffic confidential and secure by using Secure Sockets Layer (SSL) / Transport Layer Security (TLS) technology. Administrators can enable LDAP over SSL (LDAPS) by installing a properly formatted certificate from either a Microsoft certification authority (CA) or a non-Microsoft CA, according to the guidelines in Microsoft Knowledge Base Article 321051.

Is LDAP over SSL available by default?
No. Before an LDAP server can participate in an SSL session, the administrator must have obtained a digital certificate and installed it on the server. Unless this has been done, LDAP over SSL is not available.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

How could an attacker exploit the vulnerability?
An attacker could try to exploit the vulnerability by sending a specially crafted LDAP packet to a Microsoft Windows 2000 Domain Controller. Any anonymous user with access to the target network could deliver a specially crafted network packet to the affected system in order to exploit this vulnerability.

What systems are primarily at risk from the vulnerability?
LDAP is a requirement for Active Directory. Any Microsoft Windows 2000 Server that is running as an Active Directory Server is affected by this vulnerability.

What does the update do?
The update addresses the vulnerability by correctly allocating memory for specially crafted client LDAP requests.

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

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

Update Information

Detection and Deployment Tools and Guidance

Manage the software and security updates you need to deploy to the servers, desktop, and mobile systems in your organization. For more information see the TechNet Update Management Center. The Microsoft TechNet Security Web site provides additional information about security in Microsoft products.

Security updates are available from Microsoft Update, Windows Update, and Office Update. Security updates are also available from the Microsoft Download Center. You can find them most easily by doing a keyword search for "security update."

Finally, security updates can be downloaded from the Microsoft Update Catalog. The Microsoft Update Catalog provides a searchable catalog of content made available through Windows Update and Microsoft Update, including security updates, drivers and service packs. By searching using the security bulletin number (such as, “MS07-036”), you can add all of the applicable updates to your basket (including different languages for an update), and download to the folder of your choosing. For more information about the Microsoft Update Catalog, see the Microsoft Update Catalog FAQ.

Detection and Deployment Guidance

Microsoft has provided detection and deployment guidance for this month’s security updates. This guidance will also help IT professionals understand how they can use various tools to help deploy the security update, such as Windows Update, Microsoft Update, Office Update, the Microsoft Baseline Security Analyzer (MBSA), the Office Detection Tool, Microsoft Systems Management Server (SMS), and the Extended Security Update Inventory Tool. For more information, see Microsoft Knowledge Base Article 910723.

Microsoft Baseline Security Analyzer

Microsoft Baseline Security Analyzer (MBSA) allows administrators to scan local and remote systems for missing security updates as well as common security misconfigurations. For more information about MBSA, visit Microsoft Baseline Security Analyzer.

The following table provides the MBSA detection summary for this security update.

Software	MBSA 2.1
Microsoft Windows 2000 Server Service Pack 4	Yes

For more information about MBSA 2.1, see MBSA 2.1 Frequently Asked Questions.

Windows Server Update Services

By using Windows Server Update Services (WSUS), administrators can 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. For more information about how to deploy this security update using Windows Server Update Services, visit the Windows Server Update Services Web site.

Systems Management Server

The following table provides the SMS detection and deployment summary for this security update.

Software	SMS 2.0	SMS 2003 with SUSFP	SMS 2003 with ITMU	Configuration Manager 2007
Microsoft Windows 2000 Server Service Pack 4	Yes	Yes	Yes	Yes

For SMS 2.0 and SMS 2003, the SMS SUS Feature Pack (SUSFP), which includes the Security Update Inventory Tool (SUIT), can be used by SMS to detect security updates. See also Downloads for Systems Management Server 2.0.

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, see SMS 2003 Inventory Tool for Microsoft Updates. SMS 2003 can also use the Microsoft Office Inventory Tool to detect required updates for Microsoft Office applications. For more information about the Office Inventory Tool and other scanning tools, see SMS 2003 Software Update Scanning Tools. See also Downloads for Systems Management Server 2003.

System Center Configuration Manager 2007 uses WSUS 3.0 for detection of updates. For more information about Configuration Manager 2007 Software Update Management, visit System Center Configuration Manager 2007.

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

For more detailed information, see Microsoft Knowledge Base Article 910723: Summary list of monthly detection and deployment guidance articles.

Security Update Deployment


Inclusion in Future Service Packs	The update for this issue may be included in a future update rollup
Deployment
Installing without user intervention	Microsoft Windows 2000 Service Pack 4: Windows2000-kb957280-x86-enu /quiet
Installing without restarting	Microsoft Windows 2000 Service Pack 4: Windows2000-kb957280-x86-enu /norestart
Update log file	Microsoft Windows 2000 Service Pack 4: kb957280.log
Further information	See the subsection, Detection and Deployment Tools and Guidance
Restart Requirement
Restart required?	Yes, you must restart your system after you apply this security update
HotPatching	Not applicable
Removal Information	Microsoft Windows 2000 Service Pack 4: Use Add or Remove Programs tool in Control Panel or the Spuninst.exe utility located in the %Windir%\$NTUninstallKB957280$\Spuninst folder
File Information	See Microsoft Knowledge Base Article 957280
Registry Key Verification	Microsoft Windows Service Pack 4: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows 2000\SP5\KB957280\Filelist

Supported Security Update Installation Switches
Switch	Description
/help	Displays the command-line options.
Setup Modes
/passive	Unattended Setup mode. No user interaction is required, but installation status is displayed. If a restart is required at the end of Setup, a dialog box will be presented to the user with a timer warning that the computer will restart in 30 seconds.
/quiet	Quiet mode. This is the same as unattended mode, but no status or error messages are displayed.
Restart Options
/norestart	Does not restart when installation has completed.
/forcerestart	Restarts the computer after installation and force other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Presents a dialog box with a timer warning the user that the computer will restart in x seconds. (The default setting is 30 seconds.) Intended for use with the /quiet switch or the /passive switch.
/promptrestart	Displays 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 uninstall.
/forceappsclose	Forces other programs to close when the computer shuts down.
/log:path	Allows the redirection of installation log files.
/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.

Supported Spuninst.exe Switches
Switch	Description
/help	Displays the command-line options.
Setup Modes
/passive	Unattended Setup mode. No user interaction is required, but installation status is displayed. If a restart is required at the end of Setup, a dialog box will be presented to the user with a timer warning that the computer will restart in 30 seconds.
/quiet	Quiet mode. This is the same as unattended mode, but no status or error messages are displayed.
Restart Options
/norestart	Does not restart when installation has completed.
/forcerestart	Restarts the computer after installation and force other applications to close at shutdown without saving open files first.
/warnrestart[:x]	Presents a dialog box with a timer warning the user that the computer will restart in x seconds. (The default setting is 30 seconds.) Intended for use with the /quiet switch or the /passive switch.
/promptrestart	Displays 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.

Other Information

Acknowledgments

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

Paul Miseiko of nCircle for reporting the Active Directory Overflow Vulnerability (CVE-2008-4023)

Support

Customers in the U.S. and Canada can receive technical support from Microsoft Product Support Services at 1-866-PCSAFETY. There is no charge for support calls that are associated with security updates.
International customers can receive support from their local Microsoft subsidiaries. There is no charge for support that is associated with security updates. For more information about how to contact Microsoft for support issues, visit the International Support Web site.

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 14, 2008): Bulletin published.
V1.1 (October 15, 2008): Updated the Non-Affected Software table.