MSFT has released the much awaited CU5 for Exchange 2013.
You can download it here: http://www.microsoft.com/en-us/download/details.aspx?id=43103
For more info on this release?
http://blogs.technet.com/b/exchange/archive/2014/05/27/released-exchange-server-2013-cumulative-update-5.aspx
Blog to follow with upgrade details.