Vulnerability in Windows Shell Handler Could Allow Elevation of Privilege (2962488)
Published: May 13, 2014
Version: 1.0
General Information
Executive Summary
This security update resolves a privately reported vulnerability in Microsoft Windows. The vulnerability could allow elevation of privilege if an attacker runs a specially crafted application that uses ShellExecute. An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability.
This security update is rated Important for all supported releases of Windows. For more information, see the Affected and Non-Affected Software section.
The security update addresses the vulnerability by correcting the way that the ShellExecute API handles file associations in certain circumstances. For more information about the vulnerability, see the Frequently Asked Questions (FAQ) subsection for the vulnerability later in this bulletin.
Recommendation. Most 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.
The following software has 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, see Microsoft Support Lifecycle.
There are multiple updates listed for Windows 8.1 and Windows Server 2012 R2. Do I need to install all the updates?
No. Depending on how your system is configured to receive updates, only one of the updates for Windows 8.1 or Windows Server 2012 will apply.
For systems running Windows 8.1 or Windows Server 2012. R2:
The 2926765 update is for systems that already have the 2919355 update installed.
The 2962123 update is for systems without the 2919355 update installed.
For Windows 8.1 or Windows Server 2012 R2 are there any prerequisites for the 2926765 update?
Yes. Customers running Windows 8.1, Windows Server 2012 R2, or Windows RT 8.1 must first install the 2919355 update released in April, 2014 before installing the 2926765 update. For more information about the prerequisite update, see Microsoft Knowledge Base Article 2919355
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 has been tested to determine which releases are affected. Other releases are past their support life cycle. For more information about the product lifecycle, see the Microsoft Support Lifecycle website.
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 Service Pack Lifecycle Support Policy.
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 , Premier, or Authorized Contract can contact their local Microsoft sales office. For contact information, see the Microsoft Worldwide Information website, 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.
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 May bulletin summary. For more information, see Microsoft Exploitability Index.
Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software
Windows Shell File Association Vulnerability - CVE-2014-1807
Aggregate Severity Rating
Windows Server 2003
Windows Server 2003 Service Pack 2
Important Elevation of Privilege
Important
Windows Server 2003 x64 Edition Service Pack 2
Important Elevation of Privilege
Important
Windows Server 2003 with SP2 for Itanium-based Systems
Important Elevation of Privilege
Important
Windows Vista
Windows Vista Service Pack 2
Important Elevation of Privilege
Important
Windows Vista x64 Edition Service Pack 2
Important Elevation of Privilege
Important
Window Server 2008
Windows Server 2008 for 32-bit Systems Service Pack 2
Important Elevation of Privilege
Important
Windows Server 2008 for x64-based Systems Service Pack 2
Important Elevation of Privilege
Important
Windows Server 2008 for Itanium-based Systems Service Pack 2
Important Elevation of Privilege
Important
Windows 7
Windows 7 for 32-bit Systems Service Pack 1
Important Elevation of Privilege
Important
Windows 7 for x64-based Systems Service Pack 1
Important Elevation of Privilege
Important
Window Server 2008 R2
Windows Server 2008 R2 for x64-based Systems Service Pack 1
Important Elevation of Privilege
Important
Windows Server 2008 R2 for Itanium-based Systems Service Pack 1
Important Elevation of Privilege
Important
Windows 8 and Windows 8.1
Windows 8 for 32-bit Systems
Important Elevation of Privilege
Important
Windows 8 for x64-based Systems
Important Elevation of Privilege
Important
Windows 8.1 for 32-bit Systems
Important Elevation of Privilege
Important
Windows 8.1 for x64-based Systems
Important Elevation of Privilege
Important
Window Server 2012 and Windows Server 2012 R2
Windows Server 2012
Important Elevation of Privilege
Important
Windows Server 2012 R2
Important Elevation of Privilege
Important
Windows RT and Windows RT 8.1
Windows RT[1]
Important Elevation of Privilege
Important
Windows RT 8.1[1]
Important Elevation of Privilege
Important
Server Core installation option
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
Important Elevation of Privilege
Important
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)
Important Elevation of Privilege
Important
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)
Important Elevation of Privilege
Important
Windows Server 2012 (Server Core installation)
Important Elevation of Privilege
Important
Windows Server 2012 R2 (Server Core installation)
Important Elevation of Privilege
Important
Windows Shell File Association Vulnerability - CVE-2014-1807
An elevation of privilege vulnerability exists when the Windows Shell improperly handles file associations. An attacker who successfully exploited this vulnerability could run arbitrary code in the context of the Local System account. An attacker could then install programs; view, change, or delete data; or create new accounts with full administrative rights.
To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2014-1807.
Mitigating Factors
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.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
FAQ
What is the scope of the vulnerability?
This is an elevation of privilege vulnerability.
What causes the vulnerability?
The vulnerability is caused when a specially crafted application uses the ShellExecute Application Programming Interface (API) function to improperly handle file associations.
What is the Windows Shell?
The Windows user interface (UI) provides users with access to a wide variety of objects necessary for running applications and managing the operating system. The most numerous and familiar of these objects are the folders and files that reside on computer disk drives. There are also a number of virtual objects that allow the user to perform tasks such as sending files to remote printers or accessing the Recycle Bin. The Shell organizes these objects into a hierarchical namespace and provides users and applications with a consistent and efficient way to access and manage objects.
What is ShellExecute?
ShellExecute is part of the Windows Shell API functions. It performs an operation on a specified file. This could for instance mean invoking the correct handler for that specific file type. More information on the ShellExecute function can be found in the MSDN article, ShellExecute Function.
What is an Application Programming Interface (API)?
An Application Programming Interface (API) is a set of functions you can use to work with a component, application, or operating system. Typically, an API consists of one or more DLLs that provide some specific functionality.
What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could run arbitrary code in the context of the Local System account. 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 designed to elevate privileges.
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 correcting the way that the ShellExecute API handles file associations in certain circumstances.
When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through coordinated vulnerability disclosure.
When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
Yes. Microsoft is aware of limited attacks that attempt to exploit this vulnerability.
Detection and Deployment Tools and Guidance
Several resources are available to help administrators deploy security updates.
Microsoft Baseline Security Analyzer (MBSA) lets administrators scan local and remote systems for missing security updates and common security misconfigurations.
Windows Server Update Services (WSUS), Systems Management Server (SMS), and System Center Configuration Manager help administrators distribute security updates.
The Update Compatibility Evaluator components included with Application Compatibility Toolkit aid in streamlining the testing and validation of Windows updates against installed applications.
Yes, you must restart your system after you apply this security update.
Removal information
WUSA.exe does not support uninstall of updates. To uninstall an update installed by WUSA, click Control Panel, and then click Security. Under Windows Update, click View installed updates and select from the list of updates.
Yes, you must restart your system after you apply this security update.
Removal information
WUSA.exe does not support uninstall of updates. To uninstall an update installed by WUSA, click Control Panel, and then click Security. Under Windows Update, click View installed updates and select from the list of updates.
Yes, you must restart your system after you apply this security update.
Removal information
To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, and then under Windows Update, click View installed updates and select from the list of updates.
Yes, you must restart your system after you apply this security update.
Removal information
To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, and then under Windows Update, click View installed updates and select from the list of updates.
Yes, you must restart your system after you apply this security update.
Removal information
To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.
Yes, you must restart your system after you apply this security update.
Removal information
To uninstall an update installed by WUSA, use the /Uninstall setup switch or click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.
Yes, you must restart your system after you apply this security update.
Removal Information
Click Control Panel, click System and Security, click Windows Update, and then under See also, click Installed updates and select from the list of updates.
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 go to the active protections websites provided by program partners, listed in Microsoft Active Protections Program (MAPP) Partners.
Support
How to obtain help and support for this security update
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