This security update resolves a privately reported vulnerability in the JScript and VBScript scripting engines. The vulnerability could allow information disclosure if a user visited a specially crafted Web site. An attacker would have no way to force users to visit these Web sites. Instead, an attacker would have to convince users to visit the Web site, typically by getting them to click a link in an e-mail message or Instant Messenger message that takes users to the attacker's Web site.
This security update is rated Important for all supported editions of Windows 7 and Moderate for all supported editions of Windows Server 2008 R2. For more information, see the subsection, Affected and Non-Affected Software, in this section.
The security update addresses the vulnerability by correcting the manner in which the JScript and VBScript scripting engines process scripts in Web pages. For more information about the vulnerability, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.
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.