Microsoft Security Bulletin MS16-092 - Important

Security Update for Windows Kernel (3171910)

Published: July 18, 2016 | Updated: July 18, 2016

Version: 1.1

This security update resolves vulnerabilities in Microsoft Windows. The most severe of the vulnerabilities could allow security feature bypass if the Windows kernel fails to determine how a low integrity application can use certain object manager features.

This security update is rated Important for all supported releases of Microsoft Windows 8.1, Windows Server 2012, Windows Server 2012 R2, Windows RT 8.1, and Windows 10. For more information, see the Affected Software and Vulnerability Severity Ratings section.

The security update addresses the vulnerabilities by adding a validation check to the Windows kernel that determines how a low integrity application can use certain object manager features, and by correcting how the Windows kernel handles certain page fault system calls. For more information about the vulnerabilities, see the Vulnerability Information section.

For more information about this update, see Microsoft Knowledge Base Article 3171910.

The following software versions or editions are affected. Versions or editions that are not listed 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.

The severity ratings indicated for each affected software 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 July bulletin summary.

Operating System

Windows File System Security Feature Bypass - CVE-2016-3258

Windows Kernel Information Disclosure Vulnerability - CVE-2016-3272

Updates Replaced*

Windows 8.1

Windows 8.1 for 32-bit Systems
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows 8.1 for 32-bit Systems
(3169704)

Not applicable

Important 
Information Disclosure

None

Windows 8.1 for x64-based Systems
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows 8.1 for x64-based Systems
(3169704)

Not applicable

Important 
Information Disclosure

None

Windows Server 2012 and Windows Server 2012 R2

Windows Server 2012
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows Server 2012
(3169704)

Not applicable

Important 
Information Disclosure

None

Windows Server 2012 R2
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows Server 2012 R2
(3169704)

Not applicable

Important 
Information Disclosure

None

Windows RT 8.1

Windows RT 8.1[1]
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows RT 8.1[1]
(3169704)

Not applicable

Important 
Information Disclosure

None

Windows 10

Windows 10 for 32-bit Systems [2]
(3163912)

Important 
Security Feature Bypass

Important 
Information Disclosure

3163017

Windows 10 for x64-based Systems [2]
(3163912)

Important 
Security Feature Bypass

Important 
Information Disclosure

3163017

Windows 10 Version 1511 for 32-bit Systems [2]
(3172985)

Important 
Security Feature Bypass

Important 
Information Disclosure

3163018

Windows 10 Version 1511 for x64-based Systems [2]
(3172985)

Important 
Security Feature Bypass

Important 
Information Disclosure

3163018

Server Core installation option

Windows Server 2012 (Server Core installation)
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows Server 2012 (Server Core installation)
(3169704)

Not applicable

Important 
Information Disclosure

None

Windows Server 2012 R2 (Server Core installation)
(3170377)

Important 
Security Feature Bypass

Not applicable

3153171 in MS16-060

Windows Server 2012 R2 (Server Core installation)
(3169704)

Not applicable

Important 
Information Disclosure

None

[1]This update is only available via Windows Update.

[2]Windows 10 updates are cumulative. The monthly security release includes all security fixes for vulnerabilities that affect Windows 10, in addition to non-security updates. The updates are available via the Microsoft Update Catalog.

Note.The vulnerabilities discussed in this bulletin affect Windows Server 2016 Technical Preview 4 and Windows Server 2016 Technical Preview 5. An update is available for Windows Server 2016 Technical Preview 5 via Windows Update. However, no update is available for Windows Server 2016 Technical Preview 4. To be protected from the vulnerabilities, Microsoft recommends that customers running Windows Server 2016 Technical Preview 4 upgrade to Windows Server 2016 Technical Preview 5.

*The Updates Replaced column shows only the latest update in any chain of superseded updates. For a comprehensive list of updates replaced, go to the Microsoft Update Catalog, search for the update KB number, and then view update details (updates replaced information is provided on the Package Details tab).

I am running Windows Server 2012. Do I need to install the 3170377 and 3172727 updates in a particular order? 
No. The 3170377 and 3172727 updates both contain the same components and can be installed in any order. Installing one and then the other without a system restart in between is allowed; however, if you install the 3172727 update first and then restart the system, subsequent attempts to install the 3170377 update will display the message, “The update is not applicable to your computer." This is because the 3172727 update supersedes the 3170377 update by design.

Does this update contain any additional security-related changes to functionality? 
Yes. In addition to the changes that are listed for the vulnerabilities described in this bulletin, this update includes defense-in-depth updates to help improve security-related features.

Windows File System Security Feature Bypass – CVE-2016-3258

A security feature bypass vulnerability exists in the Windows kernel that could allow an attacker to exploit time of check time of use (TOCTOU) issues in file path-based checks from a low integrity application. An attacker who successfully exploited this vulnerability could potentially modify files outside of a low integrity level application.

To exploit the vulnerability, an attacker would need to take advantage of another vulnerability to compromise the sandbox process from a low integrity application. The security update addresses the vulnerability by adding a validation check on how a low integrity application can use certain object manager features.

The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:

Vulnerability title

CVE number

Publicly disclosed

Exploited

Windows File System Security Feature Bypass

CVE-2016-3258

No

No

Mitigating Factors

Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds

Microsoft has not identified any workarounds for this vulnerability.

Windows Kernel Information Disclosure Vulnerability – CVE-2016-3272

An information disclosure vulnerability exists in Microsoft Windows when the Windows kernel fails to properly handle certain page fault system calls. An authenticated attacker who successfully exploited this vulnerability could disclose information from one process to another.

To exploit the vulnerability, an attacker would have to either log on locally to an affected system, or convince a locally authenticated user to execute a specially crafted application. The update addresses this vulnerability by correcting how the Windows kernel handles certain page fault system calls.

The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:

Vulnerability title

CVE number

Publicly disclosed

Exploited

Windows Kernel Information Disclosure Vulnerability

CVE-2016-3272

Yes

No

Mitigating Factors

Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds

Microsoft has not identified any workarounds for this vulnerability.

For Security Update Deployment information, see the Microsoft Knowledge Base article referenced here in the Executive Summary.

Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgments for more information.

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.

  • V1.0 (July 18, 2016): Bulletin published.
  • V1.1 (July 18, 2016): Bulletin revised to add an Update FAQ to inform customers running Windows Server 2012 that they do not need to install the 3170377 and 3172727 updates in a particular order.
Page generated 2016-07-18 11:04-07:00.
Show: