Microsoft Security Bulletin MS08-029 – Moderate Vulnerabilities in Microsoft Malware Protection Engine Could Allow Denial of Service (952044)

Microsoft Security Bulletin MS08-029 – Moderate
Vulnerabilities in Microsoft Malware Protection Engine Could Allow Denial of Service (952044)
Published: May 13, 2008

Version: 1.0
General Information
Executive Summary

This security update resolves two privately reported vulnerabilities in the Microsoft Malware Protection Engine. An attacker could exploit either of the vulnerabilities by constructing a specially crafted file that could allow denial of service when received by the target computer system and scanned by the Microsoft Malware Protection Engine. An attacker who successfully exploited either vulnerability could cause the Microsoft Malware Protection Engine to stop responding and automatically restart.

The Microsoft Malware Protection Engine is a part of several Microsoft products. Depending upon which product is installed, this security update has different severity ratings. This security update is rated Moderate for Windows Live OneCare, Microsoft Antigen for Exchange, Microsoft Antigen for SMTP Gateway, Microsoft Windows Defender, Microsoft Forefront Client Security, Microsoft Forefront Security for Exchange Server and Microsoft Forefront Security for SharePoint. This security update is rated Low for Standalone System Sweeper located in Diagnostics and Recovery Toolset 6. For more information, see the subsection, Affected and Non-Affected Software, in this section.

The security update addresses the vulnerability by modifying the way that the Malware Protection Engine processes files. For more information about this vulnerability, see the Frequently Asked Questions (FAQ) subsection under the next section, Vulnerability Information.

Recommendation. Microsoft recommends that customers immediately ensure that they have the latest Microsoft Malware Protection Engine update. The affected software provides built-in mechanisms for the automatic detection and deployment of this update.

Known Issues. None
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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
Software Maximum Security Impact Aggregate Severity Rating

Windows Live OneCare

Denial of Service

Moderate

Microsoft Antigen for Exchange

Denial of Service

Moderate

Microsoft Antigen for SMTP Gateway

Denial of Service

Moderate

Microsoft Windows Defender

Denial of Service

Moderate

Microsoft Forefront Client Security

Denial of Service

Moderate

Microsoft Forefront Security for Exchange Server

Denial of Service

Moderate

Microsoft Forefront Security for SharePoint

Denial of Service

Moderate

Standalone System Sweeper located in Diagnostics and Recovery Toolset 6.0

Denial of Service

Low

Note These affected products provide built-in mechanisms for automatic detection and deployment of updates.
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Frequently Asked Questions (FAQ) Related to This Security Update

What is the Microsoft Malware Protection Engine?
The Microsoft Malware Protection Engine, mpengine.dll, provides the scanning, detection and cleaning capabilities for the following antivirus and antispyware clients: Windows Live OneCare, Microsoft Antigen for Exchange, Microsoft Antigen for SMTP Gateway, Microsoft Windows Defender, Microsoft Forefront Client Security, Microsoft Forefront Security for Exchange Server, Microsoft Forefront Security for SharePoint, and Standalone System Sweeper located in Diagnostics and Recovery Toolset 6 .

Are Microsoft products that use the Microsoft Malware Protection Engine automatically updated?
The affected software provides built-in mechanisms for the automatic detection and deployment of this update. Users who have disabled AutoUpdate or Microsoft Update for their Microsoft antivirus client software will need to either re-enable AutoUpdate or update the Microsoft antivirus client software manually to receive the updated Microsoft Malware Protection Engine. To update the Microsoft antivirus client software manually, users should follow the product documentation provided with the affected software.

For Microsoft Antigen and Microsoft Forefront, the Microsoft Malware Protection Engine is automatically updated. For systems that have been altered from the default installation, manual engine updates can be performed through the administrator tool. If the engine had been disabled, it can be re-enabled and then updated immediately by clicking Update Now. For customers that update engines using Microsoft Antigen Enterprise Manager, users should select Engine Update Redistribution Job and click Run Now.

Microsoft Malware Protection Engine updates for Windows Defender are distributed as part of the normal Windows Defender signature update process. For more information on how to use Windows Server Update Services (WSUS) to deploy Windows Defender definition updates, see Microsoft Knowledge Base Article 919772.

What version of the Microsoft Malware Protection Engine addresses this issue?
Affected Software Engine Version Number

Windows Live OneCare

1.1.3520.0

Microsoft Antigen for Exchange

0.1.13.192

Microsoft Antigen for SMTP Gateway

0.1.13.192

Microsoft Windows Defender

1.1.3520.0

Microsoft Forefront Client Security

1.1.3520.0

Microsoft Forefront Security for Exchange Server

0.1.13.192

Microsoft Forefront Security for SharePoint

0.1.13.192

Standalone System Sweeper located in Diagnostics and Recovery Toolset 6.0

1.1.3520.0

Note If your Microsoft Malware Protection Engine version is equal to or greater than the above listed Engine Version Number, then you are not affected by this vulnerability and do not need to take any further action.

How do I detect what version of the Microsoft Malware Protection Engine I have installed?
The section, Security Update Deployment, later in this bulletin, lists the details on how you can check which version of the Microsoft Malware Protection Engine is installed.

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.
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Vulnerability Information

Severity Ratings and Vulnerability Identifiers
Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software Microsoft Malware Protection Engine Vulnerability- CVE-2008-1437 Microsoft Malware Protection Engine Vulnerability- CVE-2008-1438 Aggregate Severity Rating
Microsoft Malware Protection Engine

Windows Live OneCare

Moderate
Denial of Service

Low
Denial of Service

Moderate

Microsoft Antigen for Exchange

Moderate
Denial of Service

Moderate
Denial of Service

Moderate

Microsoft Antigen for SMTP Gateway

Moderate
Denial of Service

Moderate
Denial of Service

Moderate

Microsoft Windows Defender

Moderate
Denial of Service

Moderate
Denial of Service

Moderate

Microsoft Forefront Client Security

Moderate
Denial of Service

Low
Denial of Service

Moderate

Microsoft Forefront Security for Exchange Server

Moderate
Denial of Service

Moderate
Denial of Service

Moderate

Microsoft Forefront Security for SharePoint

Moderate
Denial of Service

Moderate
Denial of Service

Moderate

Standalone System Sweeper located in Diagnostics and Recovery Toolset 6.0

Low
Denial of Service

Low
Denial of Service

Low
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Microsoft Malware Protection Engine Vulnerability- CVE-2008-1437

A denial of service vulnerability exists in the way that the Microsoft Malware Protection Engine processes specially crafted files. An attacker could exploit the vulnerability by constructing a specially crafted file that could allow denial of service when received by the target computer system and scanned by the Microsoft Malware Protection Engine. An attacker who successfully exploited this vulnerability could cause the Microsoft Malware Protection Engine to stop responding and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2008-1437.

Mitigating Factors for Microsoft Malware Protection Engine Vulnerability- CVE-2008-1437

Microsoft has not identified any mitigating factors for this vulnerability.
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Workarounds for Microsoft Malware Protection Engine Vulnerability- CVE-2008-1437

Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•

Microsoft Forefront Security for Exchange Server, Microsoft Forefront Security for SharePoint, and Microsoft Antigen support multiple engines in addition to the Microsoft Malware Protection Engine on a single system. If multiple engines are available on an affected system, administrators can disable the Microsoft Malware Protection Engine as a workaround, until the Microsoft Malware Protection Engine can be updated. Before disabling the Microsoft Malware Protection Engine, administrators should ensure they have installed the latest virus signatures for any third-party engine.
•

We have not identified any workarounds for Windows Live OneCare, Microsoft Windows Defender and Microsoft Forefront Client Security.
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FAQ for Microsoft Malware Protection Engine Vulnerability- CVE-2008-1437

What is the scope of the vulnerability?
A denial of service vulnerability exists in the way that the Microsoft Malware Protection Engine parses files. An attacker could exploit the vulnerability by constructing a specially crafted file that could allow denial of service when received by the target computer system and scanned by the Microsoft Malware Protection Engine.

What causes the vulnerability?
The Microsoft Malware Protection Engine does not properly validate input when parsing specially crafted files.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could make the Microsoft Malware Protection Engine non-responsive and restart.

How could an attacker exploit the vulnerability?
An attacker could try to exploit the vulnerability by creating a specially crafted file and forcing an affected system to process the file. When Microsoft Malware Protection Engine on the target machine automatically scans the file, the file could then cause the affected system to become non-responsive and restart.

An attacker could also make a specially crafted file available on a Web site. An attacker would have no way to force users to visit a particular Web site. Instead, an attacker would have to convince 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?
Any system that uses the Microsoft Malware Protection Engine is at risk from this vulnerability.

What does the update do?
The update removes the vulnerability by modifying the way that the Microsoft Malware Protection Engine processes files.

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?
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.
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Microsoft Malware Protection Engine Vulnerability- CVE-2008-1438

A denial of service vulnerability exists in the way that the Microsoft Malware Protection Engine processes specially crafted files. An attacker could exploit the vulnerability by constructing a specially crafted file that could allow denial of service when received by the target computer system and scanned by the Microsoft Malware Protection Engine. An attacker who successfully exploited this vulnerability could cause disk-space exhaustion, leading to a denial of service condition and automatic restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2008-1438.

Mitigating Factors for Microsoft Malware Protection Engine Vulnerability- CVE-2008-1438

Microsoft has not identified any mitigating factors for this vulnerability.
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Workarounds for Microsoft Malware Protection Engine Vulnerability- CVE-2008-1438

Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update. Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality:
•

Microsoft Forefront Security for Exchange Server, Microsoft Forefront Security for SharePoint, and Microsoft Antigen support multiple engines in addition to the Microsoft Malware Protection Engine on a single system. If multiple engines are available on an affected system, administrators can disable the Microsoft Malware Protection Engine as a workaround, until the Microsoft Malware Protection Engine can be updated. Before disabling the Microsoft Malware Protection Engine, administrators should ensure they have installed the latest virus signatures for any third-party engine.
•

We have not identified any workarounds for Windows Live OneCare, Microsoft Windows Defender and Microsoft Forefront Client Security.
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FAQ for Microsoft Malware Protection Engine Vulnerability- CVE-2008-1438

What is the scope of the vulnerability?
A denial of service vulnerability exists in the way that the Microsoft Malware Protection Engine parses files. An attacker could exploit the vulnerability by constructing a specially crafted file that could cause a denial of service when received by the target computer system and scanned by the Microsoft Malware Protection Engine. The denial of service results in disk-space exhaustion. After the Microsoft Malware Protection Engine has restarted, the temporary files that were created are deleted.

What causes the vulnerability?
The Microsoft Malware Protection Engine does not properly validate certain data structures when parsing files. This can cause disk-space exhaustion, leading to a denial of service condition.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could fill up a system’s disk space, making the system slow or unresponsive.

How could an attacker exploit the vulnerability?
An attacker could try to exploit the vulnerability by creating a specially crafted file and forcing an affected system to process the file. When the Microsoft Malware Protection Engine on the target machine automatically scans the file, the file could then cause the affected system to create large temporary files, filling up the system’s disk space.

An attacker could also make a specially crafted file available on a Web site. An attacker would have no way to force users to visit a particular Web site. Instead, an attacker would have to convince 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?
Any system that uses the Microsoft Malware Protection Engine is at risk from this vulnerability.

What does the update do?
The update removes the vulnerability by modifying the way that the Microsoft Malware Protection Engine processes files.

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?
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.

Other Information
Acknowledgments

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

SoWhat of Nevis Labs for reporting the Microsoft Malware Protection Engine Vulnerability (CVE-2008-1437).
•

SoWhat of Nevis Labs for reporting the Microsoft Malware Protection Engine Vulnerability (CVE-2008-1438).
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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 (May 13, 2008): Bulletin published.