Microsoft have published a Security Bulletin Summary for October 2011. Eight updates have been released including two "critical" and six "important" severity updates.

The patches address remote code execution, elevation of privilege and denial of service vulnerabilities within Windows, Internet Explorer, Microsoft .NET Framework, Microsoft Silverlight, Microsoft Forefront United Access Gateway and Microsoft Host Integration Server.

Full details here.

Security updates are available here.

Apple have published iTunes 10.5 to resolve 79 security vulnerabilities that may lead to an unexpected application termination or arbitrary code execution. Users are advised to update iTunes to patch these vulnerabilities. More information can be found at Apple's Security Advisory page.