Vulnerabilities in .NET Framework Could Allow Elevation of Privilege (2638420)
Microsoft has release a fix for a security vulnerability identified at a security conference yesterday. Since Microsoft Dynamics CRM is an ASP.NET application, any servers running CRM could be affected.
Here is a summary of the issue from the above site. Please review Microsoft’s recommendations and formulate a plan of action that makes sense for your organization.
This security update resolves one publicly disclosed vulnerability and three privately reported vulnerabilities in Microsoft .NET Framework. The most severe of these vulnerabilities could allow elevation of privilege if an unauthenticated attacker sends a specially crafted web request to the target site. An attacker who successfully exploited this vulnerability could take any action in the context of an existing account on the ASP.NET site, including executing arbitrary commands. In order to exploit this vulnerability, an attacker must be able to register an account on the ASP.NET site, and must know an existing user name.
This security update is rated Critical for Microsoft .NET Framework 1.1 Service Pack 1, Microsoft .NET Framework 2.0 Service Pack 2, Microsoft .NET Framework 3.5 Service Pack 1, Microsoft .NET Framework 3.5.1, and Microsoft .NET Framework 4 on all supported editions of Microsoft Windows. For more information, see the subsection, Affected and Non-Affected Software, in this section.
The security update addresses the vulnerabilities by correcting how the .NET Framework handles specially crafted requests, and how the ASP.NET Framework authenticates users and handles cached content. For more information about the vulnerabilities, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.
This security update also addresses the vulnerability first described in Microsoft Security Advisory 2659883.
Recommendation. The majority of customers have automatic updating enabled and will not need to take any action because this security update will be downloaded and installed automatically. Customers who have not enabled automatic updating need to check for updates and install this update manually. For information about specific configuration options in automatic updating, see Microsoft Knowledge Base Article 294871.
For administrators and enterprise installations, or end users who want to install this security update manually, Microsoft recommends that customers consider applying the security update using update management software, or by checking for updates using the Microsoft Update service.
See also the section, Detection and Deployment Tools and Guidance, later in this bulletin.
Known Issues. Microsoft Knowledge Base Article 2638420 documents the currently known issues that customers may experience when installing this security update. The article also documents recommended solutions for these issues.