Microsoft Security Bulletin MS10-021 - Important Vulnerabilities in Windows Kernel Could Allow Elevation of Privilege (979683)

Microsoft Security Bulletin MS10-021 - Important
Vulnerabilities in Windows Kernel Could Allow Elevation of Privilege (979683)
Published: April 13, 2010

Version: 1.0
General Information
Executive Summary

This security update resolves several privately reported vulnerabilities in Microsoft Windows. The most severe of these vulnerabilities could allow elevation of privilege if an attacker logged on locally and ran a specially crafted application. An attacker must have valid logon credentials and be able to log on locally to exploit these vulnerabilities. The vulnerabilities could not be exploited remotely or by anonymous users.

This security update is rated Important for all supported editions of Microsoft Windows 2000, Windows XP, Windows Server 2003, and the original release version of Windows Vista. This security update is rated Moderate for all supported versions of Windows Vista Service Pack 1 and Windows Vista Service Pack 2, Windows Server 2008, Windows 7, and Windows Server 2008 R2. For more information, see the subsection, Affected and Non-Affected Software, in this section.

The security update addresses the vulnerabilities by correcting validations, the creation of symbolic links, the resolution of virtual registry key paths, and exceptions handling. For more information about the vulnerabilities, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.

Recommendation. The majority of customers have automatic updating enabled and will not need to take any action because this security update will be downloaded and installed automatically. Customers who have not enabled automatic updating need to check for updates and install this update manually. For information about specific configuration options in automatic updating, see Microsoft Knowledge Base Article 294871.

For administrators and enterprise installations, or end users who want to install this security update manually, Microsoft recommends that customers apply the update at the earliest opportunity using update management software, or by checking for updates using the Microsoft Update service.

See also the section, Detection and Deployment Tools and Guidance, later in this bulletin.

Known Issues. Microsoft Knowledge Base Article 979683 documents the currently known issues that customers may experience when installing this security update. The article also documents recommended solutions for these issues.
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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

Elevation of Privilege

Important

MS10-015

Windows XP Service Pack 2 and Windows XP Service Pack 3

Elevation of Privilege

Important

MS10-015

Windows XP Professional x64 Edition Service Pack 2

Elevation of Privilege

Important

MS10-015

Windows Server 2003 Service Pack 2

Elevation of Privilege

Important

MS10-015

Windows Server 2003 x64 Edition Service Pack 2

Elevation of Privilege

Important

MS10-015

Windows Server 2003 with SP2 for Itanium-based Systems

Elevation of Privilege

Important

MS10-015

Windows Vista

Elevation of Privilege

Important

MS10-015

Windows Vista Service Pack 1 and Windows Vista Service Pack 2

Denial of Service

Moderate

MS10-015

Windows Vista x64 Edition

Elevation of Privilege

Important

MS10-015

Windows Vista x64 Edition Service Pack 1 and Windows Vista x64 Edition Service Pack 2

Denial of Service

Moderate

MS10-015

Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2*

Denial of Service

Moderate

MS10-015

Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2*

Denial of Service

Moderate

MS10-015

Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2

Denial of Service

Moderate

MS10-015

Windows 7 for 32-bit Systems

Denial of Service

Moderate

MS10-015

Windows 7 for x64-based Systems

Denial of Service

Moderate

None

Windows Server 2008 R2 for x64-based Systems*

Denial of Service

Moderate

None

Windows Server 2008 R2 for Itanium-based Systems

Denial of Service

Moderate

None

*Server Core installation affected. This update applies, with the same severity rating, to supported editions of Windows Server 2008 or Windows Server 2008 R2 as indicated, whether or not installed using the Server Core installation option. For more information on this installation option, see the MSDN articles, Server Core and Server Core for Windows Server 2008 R2. Note that the Server Core installation option does not apply to certain editions of Windows Server 2008 and Windows Server 2008 R2; see Compare Server Core Installation Options.
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Frequently Asked Questions (FAQ) Related to This Security Update

Where are the file information details?
Refer to the reference tables in the Security Update Deployment section for the location of the file information details.

Does this update contain the same package installation logic that was included in the security update for MS10-015?
Yes. This security update includes package detection logic that prevents the installation of the security update if certain abnormal conditions exist on 32-bit systems. These abnormal conditions on a system could be the result of an infection with a computer virus that modifies some operating system files, which renders the infected computer incompatible with the kernel update. For more information about this issue, see the Microsoft Security page, Get help with Microsoft Security Bulletin MS10-015 incompatibility message.

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 need to install this update only.

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. For more information about the product lifecycle, visit the Microsoft Support Lifecycle Web site.

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. To determine the support lifecycle for your software release, see Select a Product for Lifecycle Information. For more information about service packs for these software releases, see Lifecycle Supported Service Packs.

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 the Microsoft Worldwide Information Web site, select the country in the Contact Information list, 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 Microsoft Support Lifecycle Policy FAQ.
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Vulnerability Information

Severity Ratings and Vulnerability Identifiers

The following severity ratings assume the potential maximum impact of the vulnerability. For information regarding the likelihood, within 30 days of this security bulletin's release, of the exploitability of the vulnerability in relation to its severity rating and security impact, please see the Exploitability Index in the April bulletin summary. For more information, see Microsoft Exploitability Index.
Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software Windows Kernel Null Pointer Vulnerability - CVE-2010-0234 Windows Kernel Symbolic Link Value Vulnerability - CVE-2010-0235 Windows Kernel Memory Allocation Vulnerability - CVE-2010-0236 Windows Kernel Symbolic Link Creation Vulnerability - CVE-2010-0237 Windows Kernel Registry Key Vulnerability - CVE-2010-0238 Windows Virtual Path Parsing Vulnerability - CVE-2010-0481 Windows Kernel Malformed Image Vulnerability - CVE-2010-0482 Windows Kernel Exception Handler Vulnerability - CVE-2010-0810 Aggregate Severity Rating

Microsoft Windows 2000 Service Pack 4

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Important
Elevation of Privilege

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Important

Windows XP Service Pack 2 and Windows XP Service Pack 3

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Important
Elevation of Privilege

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Important

Windows XP Professional x64 Edition Service Pack 2

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Not applicable

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Important

Windows Server 2003 Service Pack 2

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Not applicable

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Important

Windows Server 2003 x64 Edition Service Pack 2

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Not applicable

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Important

Windows Server 2003 with SP2 for Itanium-based Systems

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Not applicable

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Important

Windows Vista

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Not applicable

Moderate
Denial of Service

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Important

Windows Vista Service Pack 1 and Windows Vista Service Pack 2

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Moderate

Windows Vista x64 Edition

Moderate
Denial of Service

Moderate
Denial of Service

Important
Elevation of Privilege

Not applicable

Moderate
Denial of Service

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Important

Windows Vista x64 Edition Service Pack 1 and Windows Vista x64 Edition Service Pack 2

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Moderate

Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2*

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Moderate

Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2*

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Moderate

Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2

Moderate
Denial of Service

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Not applicable

Moderate
Denial of Service

Moderate

Windows 7 for 32-bit Systems

Not applicable

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Moderate
Denial of Service

Not applicable

Moderate

Windows 7 for x64-based Systems

Not applicable

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Moderate
Denial of Service

Not applicable

Moderate

Windows Server 2008 R2 for x64-based Systems*

Not applicable

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Moderate
Denial of Service

Not applicable

Moderate

Windows Server 2008 R2 for Itanium-based Systems

Not applicable

Not applicable

Not applicable

Not applicable

Not applicable

Moderate
Denial of Service

Moderate
Denial of Service

Not applicable

Moderate

*Server Core installation affected. This update applies, with the same severity rating, to supported editions of Windows Server 2008 and Windows Server 2008 R2, whether or not installed using the Server Core installation option. For more information on this installation option, see the MSDN articles, Server Core and Server Core for Windows Server 2008 R2. Note that the Server Core installation option does not apply to certain editions of Windows Server 2008 and Windows Server 2008 R2; see Compare Server Core Installation Options.
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Windows Kernel Null Pointer Vulnerability - CVE-2010-0234

A denial of service vulnerability exists in the Windows kernel due to the insufficient validation of registry keys passed to a Windows kernel system call. An attacker could exploit the vulnerability by running a specially crafted application, causing the system to become unresponsive and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0234.

Mitigating Factors for Windows Kernel Null Pointer Vulnerability - CVE-2010-0234

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 Windows Kernel Null Pointer Vulnerability - CVE-2010-0234

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Null Pointer Vulnerability - CVE-2010-0234

What is the scope of the vulnerability?
This is a denial of service vulnerability. An attacker who exploited this vulnerability could cause the affected system to stop responding and automatically restart. Note that the denial of service vulnerability would not allow an attacker to run code or to elevate the attacker's user rights, but it could cause the affected system to stop accepting requests.

What causes the vulnerability?
The Windows kernel does not properly validate an argument passed to a system call.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected system to stop responding.

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 cause the system to stop responding and automatically restart.

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 addresses this vulnerability by correcting the method used for validating the argument passed to the system call.

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 when this security bulletin was originally issued.
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Windows Kernel Symbolic Link Value Vulnerability - CVE-2010-0235

A denial of service vulnerability exists in the Windows kernel due to the manner in which the kernel processes the values of symbolic links. An attacker could exploit the vulnerability by running a specially crafted application causing the system to become unresponsive and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0235.

Mitigating Factors for Windows Kernel Symbolic Link Value Vulnerability - CVE-2010-0235

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 Windows Kernel Symbolic Link Value Vulnerability - CVE-2010-0235

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Symbolic Link Value Vulnerability - CVE-2010-0235

What is the scope of the vulnerability?
This is a denial of service vulnerability. An attacker who exploited this vulnerability could cause the affected system to stop responding and automatically restart. Note that the denial of service vulnerability would not allow an attacker to run code or to elevate the attacker's user rights, but it could cause the affected system to stop accepting requests.

What causes the vulnerability?
The Windows kernel does not properly handle certain specially crafted symbolic links.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected system to stop responding.

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 cause the system to stop responding and restart.

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 addresses the vulnerability by ensuring that the Windows kernel properly validates the symbolic link values before the symbolic link can be created.

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 when this security bulletin was originally issued.
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Windows Kernel Memory Allocation Vulnerability - CVE-2010-0236

An elevation of privilege vulnerability exists in the Windows kernel due to the manner in which memory is allocated when extracting a symbolic link from a registry key. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. 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-2010-0236.

Mitigating Factors for Windows Kernel Memory Allocation Vulnerability - CVE-2010-0236

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 Windows Kernel Memory Allocation Vulnerability - CVE-2010-0236

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Memory Allocation Vulnerability - CVE-2010-0236

What is the scope of the vulnerability?
This is an elevation of privilege vulnerability. An attacker who successfully exploited this vulnerability could execute arbitrary code and 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.

What causes the vulnerability?
The Windows kernel does not correctly allocate memory when extracting the destination key from a symbolic-link type registry key.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. 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?
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 take 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 addresses the vulnerability by ensuring that the Windows kernel properly validates the symbolic link value before the symbolic link can be created.

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 when this security bulletin was originally issued.
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Windows Kernel Symbolic Link Creation Vulnerability - CVE-2010-0237

An elevation of privilege vulnerability exists when the Windows kernel does not properly restrict symbolic link creation between untrusted and trusted registry hives. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. 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-2010-0237.

Mitigating Factors for Windows Kernel Symbolic Link Creation Vulnerability - CVE-2010-0237

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:
•

This vulnerability allows an unprivileged user on a computer to run arbitrary code in the context of a user who later logs in to the same computer. The attacker cannot choose which user to impersonate.
•

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 Windows Kernel Symbolic Link Creation Vulnerability - CVE-2010-0237

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Symbolic Link Creation Vulnerability - CVE-2010-0237

What is the scope of the vulnerability?
This is an elevation of privilege vulnerability. An attacker who successfully exploited this vulnerability could execute arbitrary code and 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.

What causes the vulnerability?
The Windows kernel does not properly restrict symbolic link creation between untrusted and trusted registry hives.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. 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?
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 take 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 addresses this vulnerability by correctly blocking the traversal of symbolic links from untrusted to trusted hives.

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 when this security bulletin was originally issued.
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Windows Kernel Registry Key Vulnerability - CVE-2010-0238

A denial of service vulnerability exists in the way that the Windows kernel validates registry keys. An attacker could exploit the vulnerability by running a specially crafted application causing the system to become unresponsive and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0238.

Mitigating Factors for Windows Kernel Registry Key Vulnerability - CVE-2010-0238

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 Windows Kernel Registry Key Vulnerability - CVE-2010-0238

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Registry Key Vulnerability - CVE-2010-0238

What is the scope of the vulnerability?
This is a denial of service vulnerability. An attacker who exploited this vulnerability could cause the affected system to stop responding and automatically restart. Note that the denial of service vulnerability would not allow an attacker to run code or to elevate the attacker's user rights, but it could cause the affected system to stop accepting requests.

What causes the vulnerability?
The Windows kernel does not properly validate registry keys.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected system to stop responding.

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 cause the system to stop responding.

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 addresses this vulnerability by correcting the manner in which the Windows kernel validates registry keys.

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 when this security bulletin was originally issued.
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Windows Virtual Path Parsing Vulnerability - CVE-2010-0481

A denial of service vulnerability exists in the Windows kernel due to the way that the kernel resolves the real path for a registry key from its virtual path. An attacker could exploit the vulnerability by running a specially crafted application, causing the system to become unresponsive and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0481.

Mitigating Factors for Windows Virtual Path Parsing Vulnerability - CVE-2010-0481

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 Windows Virtual Path Parsing Vulnerability - CVE-2010-0481

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Virtual Path Parsing Vulnerability - CVE-2010-0481

What is the scope of the vulnerability?
This is a denial of service vulnerability. An attacker who exploited this vulnerability could cause the affected system to stop responding and automatically restart. Note that the denial of service vulnerability would not allow an attacker to run code or to elevate the attacker's user rights, but it could cause the affected system to stop accepting requests.

What causes the vulnerability?
The Windows kernel does not sufficiently validate a virtual path to ensure that it is valid.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected system to stop responding.

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 cause the system to stop responding and restart.

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 addresses this vulnerability by correcting the manner in which the Windows kernel resolves virtual registry key paths.

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 when this security bulletin was originally issued.
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Windows Kernel Malformed Image Vulnerability - CVE-2010-0482

A denial of service vulnerability exists in the Windows kernel due to the improper validation of specially crafted image files. An attacker could exploit the vulnerability by running a specially crafted application causing the system to become unresponsive and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0482.

Mitigating Factors for Windows Kernel Malformed Image Vulnerability - CVE-2010-0482

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 Windows Kernel Malformed Image Vulnerability - CVE-2010-0482

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Malformed Image Vulnerability - CVE-2010-0482

What is the scope of the vulnerability?
This is a denial of service vulnerability. An attacker who exploited this vulnerability could cause the affected system to stop responding and automatically restart. Note that the denial of service vulnerability would not allow an attacker to run code or to elevate the attacker's user rights, but it could cause the affected system to stop accepting requests.

What causes the vulnerability?
The Windows kernel does not properly validate the relocation section of specially crafted image files.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected system to stop responding.

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 cause the system to stop responding and restart.

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 addresses this vulnerability by correcting the manner in which the Windows kernel validates the relocation section of specially crafted image 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 when this security bulletin was originally issued.
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Windows Kernel Exception Handler Vulnerability - CVE-2010-0810

A denial of service vulnerability exists in the Windows kernel due to the way that the kernel handles certain exceptions. An attacker could exploit the vulnerability by running a specially crafted application, causing the system to become unresponsive and automatically restart.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2010-0810.

Mitigating Factors for Windows Kernel Exception Handler Vulnerability - CVE-2010-0810

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:
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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 Windows Kernel Exception Handler Vulnerability - CVE-2010-0810

Microsoft has not identified any workarounds for this vulnerability.
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FAQ for Windows Kernel Exception Handler Vulnerability - CVE-2010-0810

What is the scope of the vulnerability?
This is a denial of service vulnerability. An attacker who exploited this vulnerability could cause the affected system to stop responding and automatically restart. Note that the denial of service vulnerability would not allow an attacker to run code or to elevate the attacker's user rights, but it could cause the affected system to stop accepting requests.

What causes the vulnerability?
The Windows kernel does not properly handle certain exceptions.

What is the Windows kernel?
The Windows kernel is the core of the operating system. It provides system-level services such as device management and memory management, allocates processor time to processes, and manages error handling.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause the affected system to stop responding.

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 cause the system to stop responding and restart.

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 addresses this vulnerability by ensuring that the Windows Kernel handles the exception properly.

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 when this security bulletin was originally issued.

Other Information
Acknowledgments

Microsoft thanks the following for working with us to help protect customers:
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Matthew 'j00ru' Jurczyk and Gynvael Coldwind of Hispasec Virustotal for reporting the Windows Kernel Null Pointer Vulnerability(CVE-2010-0234)
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Matthew 'j00ru' Jurczyk and Gynvael Coldwind of Hispasec Virustotal for reporting the Windows Kernel Symbolic Link Value Vulnerability (CVE-2010-0235)
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Matthew 'j00ru' Jurczyk and Gynvael Coldwind of Hispasec Virustotal for reporting the Windows Kernel Memory Allocation Vulnerability (CVE-2010-0236)
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Gynvael Coldwind and Matthew 'j00ru' Jurczyk of Hispasec Virustotal for reporting the Windows Kernel Symbolic Link Creation Vulnerability (CVE-2010-0237)
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Matthew 'j00ru' Jurczyk and Gynvael Coldwind of Hispasec Virustotal for reporting the Windows Kernel Registry Key Vulnerability (CVE-2010-0238)
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Tavis Ormandy of Google, Inc. for reporting the Windows Virtual Path Parsing Vulnerability (CVE-2010-0481)
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Martin Tofall of Obsidium Software for reporting the Windows Kernel Malformed Image Vulnerability (CVE-2010-0482)
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Tavis Ormandy of Google, Inc. for reporting the Windows Kernel Exception Handler Vulnerability (CVE-2010-0810)
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Microsoft Active Protections Program (MAPP)

To improve security protections for customers, Microsoft provides vulnerability information to major security software providers in advance of each monthly security update release. Security software providers can then use this vulnerability information to provide updated protections to customers via their security software or devices, such as antivirus, network-based intrusion detection systems, or host-based intrusion prevention systems. To determine whether active protections are available from security software providers, please visit the active protections Web sites provided by program partners, listed in Microsoft Active Protections Program (MAPP) Partners.

Support
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Customers in the U.S. and Canada can receive technical support from Security Support or 1-866-PCSAFETY. There is no charge for support calls that are associated with security updates. For more information about available support options, see Microsoft Help and Support.
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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
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V1.0 (April 13, 2010): Bulletin published.