Published: September 13, 2016 | Updated: July 11, 2017
Version: 2.0
Executive Summary
This security update resolves vulnerabilities in Microsoft Windows. The vulnerabilities could allow elevation of privilege if an attacker runs a specially crafted application on a target system.
This security update is rated Important for all supported releases of Microsoft Windows. For more information, see the Affected Software and Vulnerability Severity Ratings section.
The security update addresses the vulnerabilities by correcting how Windows handles session objects, and by correcting how the Windows Kernel API enforces user permissions and restricts access to user information. For more information about the vulnerabilities, see the Vulnerability Information section.
Affected Software and Vulnerability Severity Ratings
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 September bulletin summary.
[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 affects Windows Server 2016 Technical Preview 5. To be protected from the vulnerability, Microsoft recommends that customers running this operating system apply the current update, which is available from Windows Update.
*The Updates Replaced column shows only the latest update in any chain of superseded updates.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).
Vulnerability Information
Multiple Windows Session Object Elevation of Privilege Vulnerabilities
Multiple Windows session object elevation of privilege vulnerabilities exist in the way that Windows handles session objects. A locally authenticated attacker who successfully exploited the vulnerabilities could hijack the session of another user.
To exploit the vulnerabilities the attacker could run a specially crafted application.
The update corrects how Windows handles session objects to prevent user session hijacking.
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 Session Object Elevation of Privilege Vulnerability
Microsoft has not identified any mitigating factors for this vulnerability.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
Windows Kernel Elevation of Privilege Vulnerability - CVE-2016-3371
An elevation of privilege vulnerability exists in the way that the Windows Kernel API enforces permissions. An attacker who successfully exploited the vulnerability could gain access to information that is not intended for the user.
To exploit the vulnerability a locally-authenticated attacker could run a specially crafted application.
The security update addresses the vulnerability by helping to ensure that the Windows Kernel API properly enforces permissions.
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 Elevation of Privilege Vulnerability
Microsoft has not identified any mitigating factors for this vulnerability.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
Windows Kernel Elevation of Privilege Vulnerability - CVE-2016-3372
An elevation of privilege vulnerability exists in the way that the Windows Kernel API enforces permissions. An attacker who successfully exploited the vulnerability could impersonate processes, interject cross-process communication, or interrupt system functionality.
To exploit the vulnerability a locally-authenticated attacker could run a specially crafted application.
The security update addresses the vulnerability by helping to ensure that the Windows Kernel API properly enforces permissions.
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 Elevation of Privilege Vulnerability
Microsoft has not identified any mitigating factors for this vulnerability.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
Windows Kernel Elevation of Privilege Vulnerability -CVE-2016-3373
An elevation of privilege vulnerability exists when the Windows Kernel API improperly allows a user to access sensitive registry information. An attacker who successfully exploited the vulnerability could gain access to user account information that is not intended for the user.
A locally-authenticated attacker could exploit this vulnerability by running a specially crafted application.
The security update addresses the vulnerability by helping to ensure that the Windows Kernel API correctly restricts access to user account information.
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 Elevation of Privilege Vulnerability
Microsoft has not identified any mitigating factors for this vulnerability.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
Security Update Deployment
For Security Update Deployment information, see the Microsoft Knowledge Base article referenced in the Executive Summary.
Acknowledgments
Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgments for more information.
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
V1.0 (September 13, 2016): Bulletin published.
V2.0 (July 11, 2017): Revised Windows Affected Software and Vulnerability Severity Ratings table to include Windows 10 Version 1703 for 32-bit Systems and Windows 10 Version 1703 for x64-based Systems because they are affected by CVE-2016-3305. Microsoft recommends that customers running Windows 10 Version 1703 should install update 4025342 to be protected from this vulnerability.