Microsoft Security Bulletin MS15-052 - Important

Vulnerability in Windows Kernel Could Allow Security Feature Bypass (3050514)

Published: May 12, 2015

Version: 1.0

Executive Summary

This security update resolves a vulnerability in Microsoft Windows. The vulnerability could allow security feature bypass if an attacker logs on to an affected system and runs a specially crafted application.

This security update is rated Important for supported editions of Windows 8, Windows Server 2012, Windows RT, Windows 8.1, Windows Server 2012 R2, and Windows RT 8.1. For more information, see the AffectedSoftware section.

The security update addresses the vulnerability by correcting the way that the Windows kernel validates the origin of the request. For more information about the vulnerability, see the Vulnerability Information section.

For more information about this update, see Microsoft Knowledge Base Article 3050514.

Affected Software

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.

Operating System Maximum Security Impact Aggregate Severity Rating Updates Replaced
Windows 8 and Windows 8.1
Windows 8 for 32-bit Systems[1] (3050514) Security Feature Bypass Important 3023562 in MS15-010
Windows 8 for x64-based Systems[1] (3050514) Security Feature Bypass Important 3023562 in MS15-010
Windows 8.1 for 32-bit Systems
(3050514)
Security Feature Bypass Important 3023562 in MS15-010
Windows 8.1 for x64-based Systems
(3050514)
Security Feature Bypass Important 3023562 in MS15-010
Windows Server 2012 and Windows Server 2012 R2
Windows Server 2012[1] (3050514) Security Feature Bypass Important 3023562 in MS15-010
Windows Server 2012 R2
(3050514)
Security Feature Bypass Important 3023562 in MS15-010
Windows RT and Windows RT 8.1
Windows RT[2] (3050514) Security Feature Bypass Important 3023562 in MS15-010
Windows RT 8.1[2] (3050514) Security Feature Bypass Important 3023562 in MS15-010
Server Core installation option
Windows Server 2012 (Server Core installation)
(3050514)
Security Feature Bypass Important 3023562 in MS15-010
Windows Server 2012 R2 (Server Core installation)
(3050514)
Security Feature Bypass Important 3023562 in MS15-010

[1]Note that update 3050514 is superseded by 3061518 in MS15-055, which is releasing concurrently. Customers who intend to install both updates manually on Windows 8 or Windows Server 2012 should install 3050514 in MS15-052 prior to installing 3061518 in MS15-055 (this is taken care of automatically for customers with automatic updating enabled). For more information, see the Known Issues section of Microsoft Knowledge Base Article 3050514.

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

Severity Ratings and Vulnerability Identifiers

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 May bulletin summary.

Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software Windows Kernel Security Feature Bypass Vulnerability - CVE-2015-1674 Aggregate Severity Rating
Windows 8 and Windows 8.1
Windows 8 for 32-bit Systems
(3050514)
Important
Security Feature Bypass
Important
Windows 8 for x64-based Systems
(3050514)
Important
Security Feature Bypass
Important
Windows 8.1 for 32-bit Systems
(3050514)
Important
Security Feature Bypass
Important
Windows 8.1 for x64-based Systems
(3050514)
Important
Security Feature Bypass
Important
Windows Server 2012 and Windows Server 2012 R2
Windows Server 2012
(3050514)
Important
Security Feature Bypass
Important
Windows Server 2012 R2
(3050514)
Important
Security Feature Bypass
Important
Windows RT and Windows RT 8.1
Windows RT
(3050514)
Important
Security Feature Bypass
Important
Windows RT 8.1
(3050514)
Important
Security Feature Bypass
Important
Server Core installation option
Windows Server 2012 (Server Core installation)
(3050514)
Important
Security Feature Bypass
Important
Windows Server 2012 R2 (Server Core installation)
(3050514)
Important
Security Feature Bypass
Important

Vulnerability Information

Windows Kernel Security Feature Bypass Vulnerability - CVE-2015-1674

A security feature bypass vulnerability exists when the Windows kernel fails to properly validate a memory address, allowing an attacker to retrieve information that could lead to a Kernel Address Space Layout Randomization (KASLR) bypass. An attacker who successfully exploited this vulnerability can then retrieve the base address of cng.sys from a compromised process.

To exploit this vulnerability, an attacker would have to log on to an affected system and run a specially crafted application. The security update addresses the vulnerability by correcting the way that the Windows kernel validates memory addresses.

Microsoft received information about this vulnerability through coordinated vulnerability disclosure. When this security bulletin was originally issued Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers.

Mitigating Factors

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 here 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 (May 12, 2015): Bulletin published.

Page generated 2015-09-16 10:08Z-07:00.