Microsoft Security Bulletin MS16-045 - Important
Security Update for Windows Hyper-V (3143118)
Published: April 12, 2016
Version: 1.0
Executive Summary
This security update resolves vulnerabilities in Microsoft Windows. The most severe of the vulnerabilities could allow remote code execution if an authenticated attacker on a guest operating system runs a specially crafted application that causes the Hyper-V host operating system to execute arbitrary code. Customers who have not enabled the Hyper-V role are not affected.
This security update is rated Important for all supported editions of Windows 8.1 for x64-based Systems, Windows Server 2012, Windows Server 2012 R2, and Windows 10 for x64-based Systems. For more information, see the Affected Software section.
The security update addresses the vulnerabilities by correcting how Hyper-V validates guest operating system user input. For more information about the vulnerabilities, see the Vulnerability Information section.
For more information about this update, see Microsoft Knowledge Base Article 3143118.
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 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.
**Affected Software** | [**Hyper-V Remote Code Execution Vulnerability - CVE-2016-0088**](http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=cve-2016-0088) | [**Hyper-V Information Disclosure Vulnerability - CVE-2016-0089**](http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=cve-2016-0089) | [**Hyper-V Information Disclosure Vulnerability - CVE-2016-0090**](http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=cve-2016-0090) | **Updates Replaced** |
**Windows 8.1** | ||||
[Windows 8.1 for x64-based Systems](https://www.microsoft.com/download/details.aspx?familyid=558c3552-1616-4f80-9784-a356f863bf51) (3135456) | **Important** Remote Code Execution | **Important** Information Disclosure | **Important** Information Disclosure | 3087088 in [MS15-105](http://go.microsoft.com/fwlink/?linkid=623539) |
**Windows Server 2012 and Windows Server 2012 R2** | ||||
[Windows Server 2012](https://www.microsoft.com/download/details.aspx?familyid=8a8fed1d-07ad-48bc-b576-cc9697510ee7) (3135456) | **Important** Remote Code Execution | **Important** Information Disclosure | Not applicable | None |
[Windows Server 2012 R2](https://www.microsoft.com/download/details.aspx?familyid=0a619af8-90c8-4bbc-81c5-0acd9a53d8cb) (3135456) | **Important** Remote Code Execution | **Important** Information Disclosure | **Important** Information Disclosure | 3087088 in [MS15-105](http://go.microsoft.com/fwlink/?linkid=623539) |
**Windows 10** | ||||
[Windows 10 for x64-based Systems](https://support.microsoft.com/kb/3147461)[1] (3147461) | **Important** Remote Code Execution | **Important** Information Disclosure | **Important** Information Disclosure | [3140745](https://support.microsoft.com/kb/3140745) |
**Server Core installation option** | ||||
[Windows Server 2012](https://www.microsoft.com/download/details.aspx?familyid=8a8fed1d-07ad-48bc-b576-cc9697510ee7) (Server Core installation) (3135456) | **Important** Remote Code Execution | **Important** Information Disclosure | Not applicable | None |
[Windows Server 2012 R2](https://www.microsoft.com/download/details.aspx?familyid=0a619af8-90c8-4bbc-81c5-0acd9a53d8cb) (Server Core installation) (3135456) | **Important** Remote Code Execution | **Important** Information Disclosure | **Important** Information Disclosure | 3087088 in [MS15-105](http://go.microsoft.com/fwlink/?linkid=623539) |
Update FAQ
I do not have Hyper-V enabled, why am I being offered this update?
The vulnerable code exists in the affected software that is listed in the affected software table. As a defense-in-depth measure, and to ensure that systems are protected if Hyper-V is enabled, the update is applicable to all supported products and versions that contain the vulnerable code.
Vulnerability Information
Hyper-V Remote Code Execution Vulnerability – CVE-2016-0088
A remote code execution vulnerability exists when Windows Hyper-V on a host server fails to properly validate input from an authenticated user on a guest operating system. To exploit the vulnerability, an attacker could run a specially crafted application on a guest operating system that could cause the Hyper-V host operating system to execute arbitrary code. Customers who have not enabled the Hyper-V role are not affected.
An attacker who successfully exploited the vulnerability could execute arbitrary code on the host operating system. The security update addresses the vulnerability by correcting how Hyper-V validates guest operating system user input.
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 |
Hyper-V Remote Code Execution Vulnerability | CVE-2016-0088 | No | No |
Vulnerability title | CVE number | Publicly disclosed | Exploited |
Hyper-V Information Disclosure Vulnerability | CVE-2016-0089 | No | No |
Hyper-V Information Disclosure Vulnerability | CVE-2016-0090 | No | No |