Microsoft Security Bulletin MS08-002 – Important Vulnerability in LSASS Could Allow Local Elevation of Privilege (943485)

Microsoft Security Bulletin MS08-002 – Important
Vulnerability in LSASS Could Allow Local Elevation of Privilege (943485)
Published: January 8, 2008

Version: 1.0
General Information
Executive Summary

This important update resolves a privately reported vulnerability in Microsoft Windows Local Security Authority Subsystem Service (LSASS). The vulnerability could allow an attacker to run arbitrary code with elevated privileges. 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.

This is an important security update for all supported editions of Windows 2000, Windows XP, and Windows Server 2003. For more information, see the subsection, Affected and Non-Affected Software, in this section.

This security update addresses the vulnerability by validating parameters passed to LSASS APIs. 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 at the earliest opportunity.

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
Operating System Maximum Security Impact Aggregate Severity Rating Bulletins Replaced by this Update

Microsoft Windows 2000 Service Pack 4

Local Elevation of privilege

Important

None

Windows XP Service Pack 2

Local Elevation of privilege

Important

None

Windows XP Professional x64 Edition and Windows XP Professional x64 Edition Service Pack 2

Local Elevation of privilege

Important

None

Windows Server 2003 Service Pack 1 and Windows Server 2003 Service Pack 2

Local Elevation of privilege

Important

None

Windows Server 2003 x64 Edition and Windows 2003 Server x64 Edition Service Pack 2

Local Elevation of privilege

Important

None

Windows Server 2003 with SP1 for Itanium-based Systems and Windows Server 2003 with SP2 for Itanium based Systems

Local Elevation of privilege

Important

None

Non-Affected Software
Operating System

Windows Vista

Windows Vista x64 Edition
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Frequently Asked Questions (FAQ) Related to This Security Update

I am using an older version 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 versions or editions are affected. Other versions or editions are past their support life cycle. To determine the support life cycle for your software version or edition, visit Microsoft Support Lifecycle.

It should be a priority for customers who have older versions or editions of the software to migrate to supported versions or editions 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 software 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
Affected Software LSASS Bypass Vulnerability - CVE-2007-5352 Aggregate Severity Rating

Microsoft Windows 2000 Service Pack 4

Important
Local Elevation of Privilege

Important

Windows XP Service Pack 2

Important
Local Elevation of Privilege

Important

Windows XP Professional x64 Edition and Windows XP Professional x64 Edition Service Pack 2

Important
Local Elevation of Privilege

Important

Windows Server 2003 Service Pack 1 and Windows Server 2003 Service Pack 2

Important
Local Elevation of Privilege

Important

Windows Server 2003 x64 Edition and Windows 2003 Server x64 Edition Service Pack 2

Important
Local Elevation of Privilege

Important

Windows Server 2003 with SP1 for Itanium-based Systems and Windows Server 2003 with SP2 for Itanium based Systems

Important
Local Elevation of Privilege

Important
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LSASS Bypass Vulnerability - CVE-2007-5352

An elevation of privilege vulnerability exists in the Microsoft Windows Local Security Authority Subsystem Service (LSASS) due to its improper handling of local procedure call (LPC) requests. The vulnerability could allow an attacker to run code with elevated privileges. 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.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2007-5352.

Mitigating Factors for LSASS Bypass Vulnerability - CVE-2007-5352

Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation:
•

An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability. The vulnerability could not be exploited remotely or by anonymous users.
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Workarounds for LSASS Bypass Vulnerability - CVE-2007-5352

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 has not identified any workarounds for this vulnerability.
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FAQ for LSASS Bypass Vulnerability - CVE-2007-5352

What is the scope of the vulnerability?
An elevation of privilege vulnerability exists in the Local Security Authority Subsystem Service (LSASS). An attacker who successfully exploited this vulnerability could run code with elevated privileges. An attacker could then take complete control of an affected system.

What causes the vulnerability?
The LSASS process does not properly handle specially crafted LPC requests. When the LSASS process receives a specially crafted LCP request it is possible for an attacker to execute code with local system privileges.

What is LSASS?
The Local Security Authority Subsystem Service (LSASS) provides an interface for managing local security, domain authentication, and Active Directory service processes. It handles authentication for the client and for the server. The LSASS also contains features that are used to support Active Directory utilities.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could gain complete control over the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full administrative rights.

How could an attacker exploit the vulnerability?
To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and gain complete control over the affected system.

What systems are primarily at risk from the vulnerability?
Workstations and terminal servers are primarily at risk. Servers could be at more risk if administrators allow users 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 validating parameters that are passed to the LSASS API, preventing access to invalid addresses.

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:
•

Thomas Garnier of SkyRecon for reporting the LSASS Bypass Vulnerability (CVE-2007-5352).
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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.
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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.
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Revisions
•

V1.0 (January 8, 2008): Bulletin published.