Microsoft Security Bulletin MS14-041 - Important

• 10/11/2017
• 19 minutes to read
• • 

Vulnerability in DirectShow Could Allow Elevation of Privilege (2975681)

Published: July 8, 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 first exploits another vulnerability in a low integrity process and then uses this vulnerability to execute specially crafted code in the context of the logged on user. By default, the modern, immersive browsing experience on Windows 8 and Windows 8.1 runs with Enhanced Protected Mode (EPM). For example, customers using the touch-friendly Internet Explorer 11 browser on modern Windows tablets are using Enhanced Protected Mode by default. Enhanced Protected Mode uses advanced security protections that can help mitigate against exploitation of this vulnerability on 64-bit systems.

This security update is rated Important for all supported editions of Windows Vista, Windows Server 2008 (excluding Itanium), Windows 7, Windows Server 2008 R2 (excluding Itanium), Windows 8, Windows 8.1, Windows Server 2012, and Windows Server 2012 R2. For more information, see the Affected and Non-Affected Software section.

The security update addresses the vulnerability by correcting how DirectShow manages objects in memory. For more information about the vulnerability, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability 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. For information about specific configuration options in automatic updating, see Microsoft Knowledge Base Article 294871. For customers who do not have automatic updating enabled, the steps in Turn automatic updating on or off can be used to enable automatic updating.

For enterprise installations, or administrators and end users who want to install this security update manually (including customers who have not enabled automatic updating), 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. The updates are also available via the download links in the Affected Software table in this bulletin.

For additional guidance, see the Detection and Deployment Tools and Guidance section in this bulletin.

Knowledge Base Article

• Knowledge Base Article: 2975681
• File Information: Yes
• SHA1/SHA2 hashes: Yes
• Known issues: None

Affected and Non-Affected Software

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.

Affected Software 

^[2]This update is for systems that do not have the 2919355 update installed. This update is not available via the Microsoft Download Center. See the Update FAQ for more information. 

Non-Affected Software

DirectShow Elevation of Privilege Vulnerability - CVE-2014-2780

A vulnerability exists in DirectShow that could allow an elevation of privilege.

To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, see CVE-2014-2780.

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:

By default, the modern, immersive browsing experience on Windows 8 and Windows 8.1 runs with Enhanced Protected Mode (EPM). For example, customers using the touch-friendly Internet Explorer 11 browser on modern Windows tablets are using Enhanced Protected Mode by default. Enhanced Protected Mode uses advanced security protections that can help mitigate against exploitation of this vulnerability on 64-bit systems. See the FAQ section for this vulnerability for more information about Enhanced Protected Mode.

Workarounds

Microsoft has not identified any workarounds for this vulnerability.

FAQ

What is the scope of the vulnerability?
This is a local elevation of privilege vulnerability.

What causes the vulnerability?
The vulnerability is caused when DirectShow improperly handles certain objects in memory, which results in the execution of code in the same context as the logged on user.

What is DirectShow?
DirectX consists of a set of low-level Application Programming Interfaces (APIs) used by Windows programs for multimedia support. Within DirectX, the DirectShow technology performs client-side audio and video sourcing, manipulation and rendering.

Microsoft DirectShow is used for streaming media on Microsoft Windows operating systems. DirectShow is used for high-quality capture and playback of multimedia streams. It automatically detects and uses video and audio acceleration hardware when available, but also supports systems without acceleration hardware. DirectShow is also integrated with other DirectX technologies. Some examples of applications that use DirectShow include DVD players, video editing applications, AVI to ASF converters, MP3 players, and digital video capture applications

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could cause code to execute within the context of the logged on user and take complete control of an affected system.

How could an attacker exploit the vulnerability?
To exploit this vulnerability an attacker would first have to have successfully exploit another vulnerability in a low integrity process and then use this vulnerability to execute specially crafted code in the context of the logged on user.

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.

Does Enhanced Protected Mode (EPM) and 64-bit processes for Enhanced Protected Mode help mitigate attacks that could attempt to exploit this vulnerability?
Yes. For Internet Explorer 10 and Internet Explorer 11, enabling Enhanced Protected Mode (EPM) and 64-bit processes for Enhanced Protected Mode helps mitigate attacks that could attempt to exploit this vulnerability on 64-bit systems. Enhanced Protected Mode does not mitigate against this vulnerability on 32-bit systems because the 64-bit processes for Enhanced Protected Mode feature is not available.

Note Enhanced Protected Mode is enabled by default for the modern, immersive browser. For Internet Explorer on the Desktop, EPM must be enabled manually.

For Internet Explorer 10 on the Desktop running on Windows 7 for x64-based systems and Windows 8 for x64-based systems, you must enable Enhanced Protected Mode (EPM). When you enable EPM on these operating systems, 64-bit processes for Enhanced Protected Mode is also enabled. There is no separate option to turn this feature on or off in Internet Explorer 10.

For Internet Explorer 11 on the Desktop running on Windows 7 for x64-based systems and Windows 8.1 for x64-based systems, you must enable both Enhanced Protected Mode (EPM) and 64-bit processes for Enhanced Protected Mode separately.

Note that after you enable Enhanced Protected Mode, incompatible add-ons will automatically be disabled. If you encounter a site that needs a disabled add-on in order to work, you can disable Enhanced Protected Mode just for that particular website. If you disable Enhanced Protected Mode for a website, any protections that EPM would provide will not apply when visiting the website. For more information about EPM, see Enhanced Protected Mode on desktop IE.

What does the update do?
The update addresses the vulnerability by correcting how DirectShow manages objects in memory.

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?
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.

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. 

For information about these and other tools that are available, see Security Tools for IT Pros. 

Security Update Deployment

Windows Vista (all editions)

Reference Table

The following table contains the security update information for this software.