Microsoft has released SQL Server 2008 Service Pack 3 Cumulative Update 11, which is Build 10.0.5840.00. There are six hotfixes in the public fix list. There is no corresponding cumulative update for earlier service pack levels for SQL Server 2008, since they are retired. If you are on SQL Server 2008, you really should be on Service Pack 3 by now (since Service Pack 2 was retired on September 17, 2012, Service Pack 1 was retired on September 19, 2011, and the RTM branch was retired on April 13, 2010). I still see a lot of servers running unsupported Service Packs of SQL Server 2008.
Remember, this cumulative update is only for SQL Server 2008 Service Pack 3. It is not for SQL Server 2008 R2.