Microsoft has released an update to address vulnerabilities in Microsoft Windows, Silverlight, Internet Explorer, .NET Framework, Office, SQL Server, Developer Tools, and Forefront as part of the Microsoft Security Bulletin Summary for October 2009. These vulnerabilities may allow an attacker to execute arbitrary code, operate with escalated privileges, cause a denial-of-service condition, or spoof an end user or website.
Source: http://www.us-cert.gov/current/index.html#microsoft_releases_october_security_bulletin1

Bulletin: http://www.microsoft.com/technet/security/Bulletin/MS09-oct.mspx

Previous news: http://www.helpmyos.com/security-news-and-updates-f9/patch-tuesday-131009-t1294.htm#3106