This is an advance notification of security bulletins that Microsoft is intending to release on October 8, 2013.
The full version of the Microsoft Security Bulletin Advance Notification for October 2013 can be found at Microsoft Security Bulletin Advance Notification for October 2013.
This bulletin advance notification will be replaced with the October bulletin summary on October 8, 2013.
Read more at source: Microsoft Security Bulletin Advance Notification for October 2013