Microsoft Security Bulletin MS16-065 - Important

Security Update for .NET Framework (3156757)

Published: May 10, 2016 | Updated: May 12, 2016

Version: 1.1

Executive Summary

This security update resolves a vulnerability in Microsoft .NET Framework. The vulnerability could cause information disclosure if an attacker injects unencrypted data into the target secure channel and then performs a man-in-the-middle (MiTM) attack between the targeted client and a legitimate server.

This security update is rated Important for Microsoft .NET Framework 2.0 Service Pack 2, Microsoft .NET Framework 3.5, Microsoft .NET Framework 3.5.1, Microsoft .NET Framework 4.5.2, Microsoft .NET Framework 4.6, and Microsoft .NET Framework 4.6.1 on affected releases of Microsoft Windows. For more information, see the Affected Software section.

The security update addresses the vulnerability by modifying the way that the .NET encryption component sends and receives encrypted network packets. For more information about the vulnerability, see the Vulnerability Information section.

For more information about this update, see Microsoft Knowledge Base Article 3156757.

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 May bulletin summary.

**Operating System** **Component** [**TLS/SSL Information Disclosure Vulnerability - CVE-2016-0149**](http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=cve-2016-0149) **Updates Replaced**
**Windows Vista**
Windows Vista Service Pack 2 [Microsoft .NET Framework 2.0 Service Pack 2](https://www.microsoft.com/downloads/details.aspx?familyid=76aad4f4-34b0-4f90-81c2-26d1275a6cb1) (3142023) **Important** Information Disclosure None
Windows Vista Service Pack 2 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Vista Service Pack 2 [Microsoft .NET Framework 4.6](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
Windows Vista x64 Edition Service Pack 2 [Microsoft .NET Framework 2.0 Service Pack 2](https://www.microsoft.com/downloads/details.aspx?familyid=76aad4f4-34b0-4f90-81c2-26d1275a6cb1) (3142023) **Important** Information Disclosure None
Windows Vista x64 Edition Service Pack 2 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Vista x64 Edition Service Pack 2 [Microsoft .NET Framework 4.6](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
**Windows Server 2008**
Windows Server 2008 for 32-bit Systems Service Pack 2 [Microsoft .NET Framework 2.0 Service Pack 2](https://www.microsoft.com/downloads/details.aspx?familyid=76aad4f4-34b0-4f90-81c2-26d1275a6cb1) (3142023) **Important** Information Disclosure None
Windows Server 2008 for 32-bit Systems Service Pack 2 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2008 for 32-bit Systems Service Pack 2 [Microsoft .NET Framework 4.6](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
Windows Server 2008 for x64-based Systems Service Pack 2 [Microsoft .NET Framework 2.0 Service Pack 2](https://www.microsoft.com/downloads/details.aspx?familyid=76aad4f4-34b0-4f90-81c2-26d1275a6cb1) (3142023) **Important** Information Disclosure None
Windows Server 2008 for x64-based Systems Service Pack 2 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2008 for x64-based Systems Service Pack 2 [Microsoft .NET Framework 4.6](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
Windows Server 2008 for Itanium-based Systems Service Pack 2 [Microsoft .NET Framework 2.0 Service Pack 2](https://www.microsoft.com/downloads/details.aspx?familyid=76aad4f4-34b0-4f90-81c2-26d1275a6cb1) (3142023) **Important** Information Disclosure None
**Windows 7**
Windows 7 for 32-bit Systems Service Pack 1 [Microsoft .NET Framework 3.5.1](https://www.microsoft.com/downloads/details.aspx?familyid=f4bd9640-f2f5-4510-9a1e-935eee95414c) (3142024) **Important** Information Disclosure None
Windows 7 for 32-bit Systems Service Pack 1 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows 7 for 32-bit Systems Service Pack 1 [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
Windows 7 for x64-based Systems Service Pack 1 [Microsoft .NET Framework 3.5.1](https://www.microsoft.com/downloads/details.aspx?familyid=f4bd9640-f2f5-4510-9a1e-935eee95414c) (3142024) **Important** Information Disclosure None
Windows 7 for x64-based Systems Service Pack 1 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows 7 for x64-based Systems Service Pack 1 [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
**Windows Server 2008 R2**
Windows Server 2008 R2 for x64-based Systems Service Pack 1 [Microsoft .NET Framework 3.5.1](https://www.microsoft.com/downloads/details.aspx?familyid=f4bd9640-f2f5-4510-9a1e-935eee95414c) (3142024) **Important** Information Disclosure None
Windows Server 2008 R2 for x64-based Systems Service Pack 1 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2008 R2 for x64-based Systems Service Pack 1 [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
Windows Server 2008 R2 for Itanium-based Systems Service Pack 1 [Microsoft .NET Framework 3.5.1](https://www.microsoft.com/downloads/details.aspx?familyid=f4bd9640-f2f5-4510-9a1e-935eee95414c) (3142024) **Important** Information Disclosure None
**Windows 8.1**
Windows 8.1 for 32-bit Systems [Microsoft .NET Framework 3.5](https://www.microsoft.com/downloads/details.aspx?familyid=e2027350-fb9c-4f7e-92f8-5c48cde471bb) (3142026) **Important** Information Disclosure None
Windows 8.1 for 32-bit Systems [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=b1045ebd-be10-4d7f-8953-6a24a99ab938)[1] (3142030) **Important** Information Disclosure 2978041 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows 8.1 for 32-bit Systems [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=356d1027-92cd-42a3-816b-a5d757445480)[1] (3142036) **Important** Information Disclosure None
Windows 8.1 for x64-based Systems [Microsoft .NET Framework 3.5](https://www.microsoft.com/downloads/details.aspx?familyid=e2027350-fb9c-4f7e-92f8-5c48cde471bb) (3142026) **Important** Information Disclosure None
Windows 8.1 for x64-based Systems [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=b1045ebd-be10-4d7f-8953-6a24a99ab938)[1] (3142030) **Important** Information Disclosure 2978041 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows 8.1 for x64-based Systems [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=356d1027-92cd-42a3-816b-a5d757445480)[1] (3142036) **Important** Information Disclosure None
**Windows Server 2012 and Windows Server 2012 R2**
Windows Server 2012 [Microsoft .NET Framework 3.5](https://www.microsoft.com/downloads/details.aspx?familyid=af916e33-3355-4162-825d-1d84e9198b1b) (3142025) **Important** Information Disclosure None
Windows Server 2012 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=41cbcfd9-ebde-4565-856f-d1bf73ea2ca4)[1] (3142032) **Important** Information Disclosure 2978042 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2012 [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=a51422ea-3234-4e4d-a502-761a11ce84d4)[1] (3142035) **Important** Information Disclosure None
Windows Server 2012 R2 [Microsoft .NET Framework 3.5](https://www.microsoft.com/downloads/details.aspx?familyid=e2027350-fb9c-4f7e-92f8-5c48cde471bb) (3142026) **Important** Information Disclosure None
Windows Server 2012 R2 [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=b1045ebd-be10-4d7f-8953-6a24a99ab938)[1] (3142030) **Important** Information Disclosure 2978041 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2012 R2 [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=356d1027-92cd-42a3-816b-a5d757445480)[1] (3142036) **Important** Information Disclosure None
**Windows RT 8.1**
Windows RT 8.1 Microsoft .NET Framework 4.5.2[1][2] (3142030) **Important** Information Disclosure 2978041 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows RT 8.1 Microsoft .NET Framework 4.6/4.6.1[1][2] (3142036) **Important** Information Disclosure None
**Windows 10**
[Windows 10 for 32-bit Systems](https://support.microsoft.com/kb/3156387)[3] (3156387) Microsoft .NET Framework 3.5 **Important** Information Disclosure [3147458](https://support.microsoft.com/kb/3147458)
[Windows 10 for 32-bit Systems](https://support.microsoft.com/kb/3156387)[3] (3156387) Microsoft .NET Framework 4.6 **Important** Information Disclosure [3147458](https://support.microsoft.com/kb/3147458)
[Windows 10 for x64-based Systems](https://support.microsoft.com/kb/3156387)[3] (3156387) Microsoft .NET Framework 3.5 **Important** Information Disclosure [3147458](https://support.microsoft.com/kb/3147458)
[Windows 10 for x64-based Systems](https://support.microsoft.com/kb/3156387)[3] (3156387) Microsoft .NET Framework 4.6 **Important** Information Disclosure [3147458](https://support.microsoft.com/kb/3147458)
[Windows 10 Version 1511 for 32-bit Systems](https://support.microsoft.com/kb/3156421)[2] (3156421) Microsoft .NET Framework 3.5 **Important** Information Disclosure [3140768](https://support.microsoft.com/kb/3140768)
[Windows 10 Version 1511 for 32-bit Systems](https://support.microsoft.com/kb/3156421) [2] (3156421) Microsoft .NET Framework 4.6.1 **Important** Information Disclosure [3140768](https://support.microsoft.com/kb/3140768)
[Windows 10 Version 1511 for x64-based Systems](https://support.microsoft.com/kb/3156421)[2] (3156421) Microsoft .NET Framework 3.5 **Important** Information Disclosure [3140768](https://support.microsoft.com/kb/3140768)
[Windows 10 Version 1511 for x64-based Systems](https://support.microsoft.com/kb/3156421) [2] (3156421) Microsoft .NET Framework 4.6.1 **Important** Information Disclosure [3140768](https://support.microsoft.com/kb/3140768)
**Server Core installation option**
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) [Microsoft .NET Framework 3.5.1](https://www.microsoft.com/downloads/details.aspx?familyid=f4bd9640-f2f5-4510-9a1e-935eee95414c) (3142024) **Important** Information Disclosure None
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=cd711144-c95e-4a08-baa0-09dc1d65f57a)[1] (3142033) **Important** Information Disclosure 2972107 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=01690bdc-f88c-4997-9383-41b273476639)[1] (3142037) **Important** Information Disclosure None
Windows Server 2012 (Server Core installation) [Microsoft .NET Framework 3.5](https://www.microsoft.com/downloads/details.aspx?familyid=af916e33-3355-4162-825d-1d84e9198b1b) (3142025) **Important** Information Disclosure None
Windows Server 2012 (Server Core installation) [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=41cbcfd9-ebde-4565-856f-d1bf73ea2ca4)[1] (3142032) **Important** Information Disclosure 2978042 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2012 (Server Core installation) [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=a51422ea-3234-4e4d-a502-761a11ce84d4)[1] (3142035) **Important** Information Disclosure None
Windows Server 2012 R2 (Server Core installation) [Microsoft .NET Framework 3.5](https://www.microsoft.com/downloads/details.aspx?familyid=e2027350-fb9c-4f7e-92f8-5c48cde471bb) (3142026) **Important** Information Disclosure None
Windows Server 2012 R2 (Server Core installation) [Microsoft .NET Framework 4.5.2](https://www.microsoft.com/downloads/details.aspx?familyid=b1045ebd-be10-4d7f-8953-6a24a99ab938)[1] (3142030) **Important** Information Disclosure 2978041 in [MS14-057](http://go.microsoft.com/fwlink/?linkid=513095)
Windows Server 2012 R2 (Server Core installation) [Microsoft .NET Framework 4.6/4.6.1](https://www.microsoft.com/downloads/details.aspx?familyid=356d1027-92cd-42a3-816b-a5d757445480)[1] (3142036) **Important** Information Disclosure None
[1]For information about changes in support for .NET Framework 4.x, see [Internet Explorer and .NET Framework 4.x Support Announcements](http://support2.microsoft.com/gp/msl-ie-dotnet-an/en).

[2]Windows RT 8.1 updates are available only via Windows Update.

[3]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 Windows Server 2016 Technical Preview 5 is affected. Customers running this operating system are encouraged to apply the update, which is available via Windows Update.

Vulnerability Information

TLS/SSL Information Disclosure Vulnerability - CVE-2016-0149

An information disclosure vulnerability exists in the TLS/SSL protocol, implemented in the encryption component of Microsoft .NET Framework. An attacker who successfully exploited this vulnerability could decrypt encrypted SSL/TLS traffic.

To exploit the vulnerability, an attacker would first have to inject unencrypted data into the secure channel and then perform a man-in-the-middle (MiTM) attack between the targeted client and a legitimate server. The update addresses the vulnerability by modifying the way that the .NET encryption component sends and receives encrypted network packets.

Important Microsoft recommends that customers download and test the applicable update in controlled/managed environments before deploying it in their production environments.

In case of application compatibility issues, the recommended approach is to ensure that the server and client endpoints are correctly implementing the TLS RFC, and that they can interpret two split records containing 1, n-1 bytes respectively after this update. For more information and developer guidance, see Microsoft Knowledge Base Article 3155464.

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
TLS/SSL Information Disclosure Vulnerability CVE-2016-0149 Yes No
### Mitigating Factors The following [mitigating factors](https://technet.microsoft.com/library/security/dn848375.aspx) may be helpful in your situation: Customers who have enabled TLS1.2 are not affected. For more information and developer guidance, see [Microsoft Knowledge Base Article 3155464](https://support.microsoft.com/kb/3155464). ### Workarounds Microsoft has not identified any [workarounds](https://technet.microsoft.com/library/security/dn848375.aspx) 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](https://technet.microsoft.com/library/security/mt674627.aspx) 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 (May 10, 2016): Bulletin published. - V1.1 (May 12, 2016): Revised bulletin to announce a detection change for the 3142037 update for .NET Framework 4.6/4.6.1. This is an informational change only. Customers who have already successfully updated their systems do not need to take any action. *Page generated 2016-05-12 09:54-07:00.*