Microsoft released a security update for SharePoint 2007 and 2010.
You can find more details about the security update in the following articles:
- http://support.microsoft.com/kb/2596911 (2007)
- http://support.microsoft.com/kb/2695502 (2010)
After installing the fixes it is required to run the SharePoint configuration wizzard.
Related Update Centers:
- Update Center for Microsoft Office, Office Servers, and Related Products
- Updates for SharePoint Server 2010 and SharePoint Foundation 2010
- Updates for Project Server 2010
- Updates for Enterprise Search Products