Microsoft Security Response Center Blog Alerts

Revision Note: V1.0 (November 10, 2015): Advisory published.
Summary: Microsoft is announcing the availability of a security update for Windows Hyper-V to protect against a denial of service condition that can be triggered with certain central processing unit (CPU) chipsets. Although the weakness resides in the chipset, Microsoft is issuing this security update to protect customers. The update prevents guests on a Hyper-V system from triggering a weakness in the CPU that could allow instructions from a Hyper-V guest to place its Hyper-V host’s CPU into an unresponsive state, leading to a denial of service condition for the guest operating systems running on the affected host. Successful exploitation of the CPU weakness would require kernel-mode code execution privileges on the guest operating system.

Revision Note: V2.0 (October 13, 2015): Advisory revised to broaden the affected software list to include Windows 10 systems that are running .NET Framework 3.5 applications and systems with .NET Framework 4.6 installed that are running .NET Framework 4.5/4.5.1/4.5.2 applications, and to provide customers running these configurations with steps for manually disabling RC4 in TLS. See the Affected Software and Suggested Actions sections of this advisory for more information.
Summary: On May 13, 2014, Microsoft announced the availability of an update for Microsoft .NET Framework that disables RC4 in Transport Layer Security (TLS) through the modification of the system registry. Use of RC4 in TLS could allow an attacker to perform man-in-the-middle attacks and recover plaintext from encrypted sessions.

Revision Note: V2.0 (October 13, 2015): Advisory revised to notify customers that an update is available that modifies the Code Integrity component in Windows to extend trust removal for the four digital certificates addressed by this advisory to also preclude kernel-mode code signing.
Summary: Microsoft is aware of four digital certificates that were inadvertently disclosed by D-Link Corporation that could be used in attempts to spoof content. The disclosed end-entity certificates cannot be used to issue other certificates or impersonate other domains, but could be used to sign code. This issue affects all supported releases of Microsoft Windows.

Revision Note: V1.1 (October 13, 2015): Advisory revised to announce that the Default Cipher Suite Prioritization update (3042058), originally released May 12, 2015 via the Microsoft Download Center (DLC) only, is now also available via Microsoft Update (MU) and Windows Server Update Services (WSUS). This is an update offering venue change only. There were no changes to the update files. Customers who have already successfully installed the update do not need to take any action.
Summary: On May 12, 2015, Microsoft announced the availability of an update to cryptographic cipher suite prioritization in Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, Windows 8.1, and Windows Server 2012 R2. The update added additional cipher suites to the default list on affected systems and improved cipher suite priority ordering. The improvements were in keeping with ongoing efforts to bolster the effectiveness of encryption in Windows operating systems.

Revision Note: V1.0 (September 8, 2015):
Summary: Microsoft is announcing the availability of a defense-in-depth update that improves the enforcement of publisher rules by Windows AppLocker in Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, Windows 8.1, and Windows Server 2012 R2. The improvement is part of ongoing efforts to bolster the effectiveness of security controls in Windows.

Severity Rating: Important
Revision Note: V1.0 (July 14, 2015): Advisory published
Summary: Microsoft is releasing this security advisory to inform customers that an update to the Microsoft Malicious Software Removal Tool (MSRT) is available that addresses a security vulnerability that was reported to Microsoft. The vulnerability could allow elevation of privilege if an attacker logs on to a target system and places a specially crafted dynamic link library (.dll) file in a local directory. An authenticated attacker who successfully exploited the vulnerability could elevate privileges on a target system. An attacker could then install programs; view, change, or delete data; or create new accounts with full administrative rights.

Revision Note: V2.0 (June 9, 2015): Added the 3062760 update to the Juniper VPN Client Update section.
Summary: Microsoft is announcing the availability of an update for the Juniper Networks Windows In-Box Junos Pulse Client for Windows 8.1 and Windows RT 8.1. The update addresses a vulnerability in the Juniper VPN client by updating the affected Juniper VPN client libraries contained in affected versions of Microsoft Windows.

Revision Note: V1.0 (May 1, 2015): V1.0 (May 1, 2015): Advisory published.
Summary: Microsoft is offering the Local Administrator Password Solution (LAPS) that provides a solution to the issue of using a common local account with an identical password on every computer in a domain. LAPS resolves this issue by setting a different, random password for the common local administrator account on every computer in the domain. Domain administrators using the solution can determine which users, such as helpdesk administrators, are authorized to read passwords.

Revision Note: V3.0 (April 14, 2015): Revised advisory to announce with the release of security update 3038314 on April 14, 2015 SSL 3.0 is disabled by default in Internet Explorer 11, and to add instructions for how to undo the workarounds.
Summary: Microsoft is aware of detailed information that has been published describing a new method to exploit a vulnerability in SSL 3.0. This is an industry-wide vulnerability affecting the SSL 3.0 protocol itself and is not specific to the Windows operating system. All supported versions of Microsoft Windows implement this protocol and are affected by this vulnerability. Microsoft is not aware of attacks that try to use the reported vulnerability at this time. Considering the attack scenario, this vulnerability is not considered high risk to customers.

Revision Note: V1.0 (April 14, 2015): Advisory published.
Summary: Microsoft is announcing the availability of a defense-in-depth update that improves the authentication used by the Public Key Cryptography User-to-User (PKU2U) security support provider (SSP) in Windows 8.1, Windows Server 2012 R2, and Windows RT 8.1. The improvement is part of ongoing efforts to bolster the effectiveness of security controls in Windows.