Microsoft Windows contains a vulnerability that could allow a local attacker to execute arbitrary code on a targeted system with elevated privileges. Updates are available.
Description
Microsoft Windows contains a vulnerability that could allow a local attacker to execute arbitrary code with elevated privileges.
The vulnerability is due to improper validation of objects by the Windows kernel. A local attacker could exploit this vulnerability by running a program that is designed to send malicious requests to an affected system. If successful, the attacker could execute arbitrary code with elevated privileges.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
Warning Indicators
The following Microsoft systems are affected:
Windows XP SP3 and prior
Windows XP Professional x64 Edition SP2 and prior
Windows Server 2003 SP2 and prior
Windows Server 2003 x64 Edition SP2 and prior
Windows Server 2003 for Itanium-based Systems SP2 and prior
Windows Vista SP2 and prior
Windows Vista x64 Edition SP2 and prior
Windows Server 2008 for 32-bit Systems SP2 and prior
Windows Server 2008 for x64-based Systems SP2 and prior
Windows Server 2008 for Itanium-based Systems SP2 and prior
Windows 7 for 32-bit Systems SP1 and prior
Windows 7 for x64-based Systems SP1 and prior
Windows Server 2008 R2 for x64-based Systems SP1 and prior
Windows Server 2008 R2 for Itanium-based Systems SP1 and prior
IntelliShield Analysis
Microsoft announced the vulnerability as part of a group of similar flaws in affected products. Few details are available to distinguish the vulnerabilities from one another.
However, mitigating factors common to each vulnerability diminish the potential for exploitation. An attacker could exploit each vulnerability only by first gaining local access to a vulnerable system, limiting the source of exploits to current users of affected systems. Systems with multiple users are most at risk because these users may attempt to exploit the system to gain additional access or view files from other system users. Systems under the logical administrative or physical control of a single user would suffer little practical impact in the event of an exploit because the user already has logical privileges to gain complete control over the system or the physical means to subvert any logical controls.
The Cisco Applied Intelligence team has created an Applied Mitigation Bulletin to address vulnerabilities that Microsoft disclosed in the April 2011 security bulletin release. This Cisco bulletin, which assists administrators in identifying or mitigating these vulnerabilities using Cisco devices, is available at the following link: Cisco Applied Mitigation Bulletin: Microsoft Security Bulletin Release for April 2011
Vendor Announcements
Microsoft has released a security bulletin at the following link: MS11-034
Impact
A local attacker could exploit this vulnerability to execute arbitrary code on the system with elevated privileges, possibly resulting in a complete system compromise.
Technical Information
The vulnerability is due to improper object management by the Windows win32k.sys kernel driver. A local attacker could exploit the vulnerability by running a malicious program that is designed to trigger a use-after-free error. If successful, the attacker could take advantage of the error condition to execute arbitrary code with the privileges of the Windows kernel.
Additional technical information is not available.
Safeguards
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to access local systems.
Administrators are advised to implement physical security for production servers.
Administrators may consider using the Microsoft Baseline Security Analyzer (MBSA) scan tool to identify common security misconfigurations and missing security updates on system endpoints.
Administrators are advised to monitor critical systems.
Patches/Software
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Windows Update website. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
Home Edition Base, SP1, SP2, SP3 | Professional Edition Base, SP1, SP2, SP3 | Professional x64 (AMD/EM64T) Base, SP2
Associated Products:
N/A
Alerts and bulletins on the Cisco Security Intelligence Operations Portal are highlighted by analysts in the
Cisco Threat Operations Center and represent a subset of the comprehensive content that is available through Cisco Security IntelliShield Alert Manager Service.
This customizable threat and vulnerability alert service provides security staff with access to timely, accurate, and credible information about threats and vulnerabilities that may affect their environment. Cisco is pleased to offer a free trial of the service.
To register for full access, please visit the IntelliShield trial registration page.
LEGAL DISCLAIMER The urgency and severity ratings of this alert are not tailored to individual users; users may value alerts differently based upon their network configurations and circumstances. THE ALERT, AND INFORMATION CONTAINED THEREIN, ARE PROVIDED ON AN "AS IS" BASIS AND DO NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE ALERT, AND INFORMATION CONTAINED THEREIN, OR MATERIALS LINKED FROM THE ALERT, IS AT YOUR OWN RISK. INFORMATION IN THIS ALERT AND ANY RELATED COMMUNICATIONS IS BASED ON OUR KNOWLEDGE AT THE TIME OF PUBLICATION AND IS SUBJECT TO CHANGE WITHOUT NOTICE. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE ALERTS AT ANY TIME.
