Microsoft .NET Framework contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system. Updates are available.
Description
Microsoft .NET Framework contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code.
The vulnerability is due to improper handling of external dynamic-link library (DLL) files by the .NET Framework. An unauthenticated, remote attacker could exploit the vulnerability by convincing a user to open a malicious .NET application. If successful, the attacker could execute arbitrary code on the system with the privileges of the user.
Microsoft confirmed the vulnerability in a security bulletin and released software updates.
Warning Indicators
The following Microsoft products are affected:
Microsoft .NET Framework 1.0 SP3 when installed on the following:
Windows XP Tablet PC Edition 2005 SP3
Windows XP Media Center Edition 2005 SP3
Microsoft .NET Framework versions 1.1 SP1, 2.0 SP2, and 4 when installed on the following:
Windows XP SP3, Professional x64 Edition SP2
Windows Server 2003 SP2, x64 Edition SP2 and for Itanium-based Systems SP2
Windows Vista SP2 and x64 Edition SP2
Windows Server 2008 (32-bit, x64 and Itanium) SP2
Windows 7 for (32-bit and x64) SP1 and prior (.NET Framework versions 3.5.1 and 4 only)
Windows Server 2008 R2 (x64 and Itanium) SP1 and prior (.NET Framework versions 3.5.1 and 4 only)
Microsoft .NET Framework 3.5 when installed on the following:
Windows 8 (32-bit and x64)
Windows Server 2012
Windows RT
IntelliShield Analysis
To exploit the vulnerability, the attacker may provide a link that directs a user to a file and use misleading language or instructions to persuade the user to follow the provided link. The attacker may require access to a network directory to place the crafted DLL. This requirement may reduce the likelihood of a successful exploit.
Microsoft has corrected this vulnerability by modifying the way the Microsoft .NET Framework loads external DLLs.
The Cisco Applied Intelligence team has created an Applied Mitigation Bulletin to address vulnerabilities that Microsoft disclosed in the November 2012 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 November 2012
Vendor Announcements
Microsoft has released a security bulletin at the following link: MS12-074
Impact
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary code on a targeted system with the privileges of the user. If the user holds elevated privileges, the attacker could gain complete control of the system.
Technical Information
The vulnerability exists because the Entity Framework, which is a component of the affected software and is built with ADO.NET, enforces incorrect path restrictions when loading external libraries.
An unauthenticated, remote attacker could exploit the vulnerability by hosting a crafted DLL in a network directory that also contains an application that is built with ADO.NET and convincing a user to open the .NET application. When the application is executed, it may attempt to load the malicious DLL and execute any code it contains. A successful exploit could allow the attacker to execute arbitrary code on the system with the privileges of the user. If the user holds elevated privileges, the attacker could gain complete control over the system.
Safeguards
Administrators are advised to apply the appropriate updates.
Users are advised not to open e-mail messages from suspicious or unrecognized sources. If users cannot verify that links or attachments included in e-mail messages are safe, they are advised not to open them.
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 affected 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 Microsoft Update service. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
Datacenter Edition SP2 | Datacenter Edition, 64-bit SP2 | Enterprise Edition SP2 | Enterprise Edition, 64-bit SP2 | Essential Business Server Premium SP2 | Essential Business Server Premium, 64-bit SP2 | Essential Business Server Standard SP2 | Itanium-Based Systems Edition SP2 | Standard Edition SP2 | Standard Edition, 64-bit SP2 | Web Server SP2 | Web Server, 64-bit SP2
Microsoft, Inc.
Windows Server 2008 R2
Itanium-Based Systems Edition Base, SP1 | x64-Based Systems Edition Base, SP1
Microsoft, Inc.
Windows Server 2012
Original Release Base
Microsoft, Inc.
Windows Vista
Business SP2 | Business x64 Edition SP2 | Enterprise SP2 | Enterprise x64 Edition SP2 | Home Basic SP2 | Home Basic x64 Edition SP2 | Home Premium SP2 | Home Premium x64 Edition SP2 | Ultimate SP2 | Ultimate x64 Edition SP2
Microsoft, Inc.
Windows XP
Home Edition SP3 | Media Center Edition SP3 | Professional Edition SP3 | Professional x64 (AMD/EM64T) SP2
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