Vulnerability in JScript Scripting Engine Could Allow Remote Code Execution
Description: This security update resolves a privately reported vulnerability in the JScript scripting engine that could allow remote code execution if a user opened a specially crafted file or visited a specially crafted Web site and invoked a malformed script. If a user is logged on with administrative user rights, an attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. This security update addresses the vulnerability by modifying the way that the JScript engine processes scripts in Web pages.
Update type: Critical
Release date: September 8, 2009
Applies to: All versions
Knowledge base: http://support.microsoft.com/kb/971961
- JScript Remote Code Execution Vulnerability – CVE-2009-1920
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB971961.