Additional technical information to describe the Microsoft .NET Framework parameter validation arbitrary code execution vulnerability is available.
Microsoft .NET Framework contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system.
The vulnerability is due to improper validation of certain parameters by the .NET Framework. An unauthenticated, remote attacker could exploit the vulnerability by convincing a user to visit a malicious website. If successful, the attacker could execute arbitrary code on the system with the privileges of the user.
Proof-of-concept code that exploits this vulnerability is publicly available.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
Microsoft .NET Framework versions 1.0 SP3, 1.1 SP1, 2.0 SP2, 3.5.1, and 4.0 are vulnerable when running on the following systems:
Windows XP Tablet Edition 2005 SP3 and prior
Windows XP Media Center Edition 2005 SP3 and prior
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 Itanium-based Edition 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 and Windows 7 for 32-bit Systems SP1 and prior
Windows 7 for x64-based Systems and 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
To exploit the vulnerability, the attacker may provide a file or a link to a malicious website and use misleading language or instructions to persuade the user to open the file or follow the provided link.
Microsoft has corrected this vulnerability by correcting the manner in which parameters are validated by the .NET Framework.
Microsoft has released a security bulletin at the following link: MS12-025†
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary code on an affected system with the privileges of the user. If the user holds elevated privileges, the attacker could gain complete control over the system.
The vulnerability is due to improper input handling by the GraphicsPathIterator class, that is used to call native Windows Graphics Device Interface (GDI+) library functions. When calling native GDI+ functions, the affected class could perform insufficient sanitization on the input that is received via certain unspecified parameters, leading to a corrupt memory condition.
An unauthenticated, remote attacker could exploit the vulnerability by convincing a user to visit a malicious web page. Processing the malicious web page could trigger a memory corruption error, that could allow the attacker to execute arbitrary code on the system under the security context of the targeted user.
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 disabling XAML browser applications in Internet Explorer.
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.
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.
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.