We have also released the Service Pack 1 for Exchange Server 2013.
You can read the full details at :
Released: Exchange Server 2013 Service Pack 1 - Exchange Team Blog - Site Home - TechNet Blogshttp://blogs.technet.com/b/exchange/archive/2014/02/25/exchange-server-2013-service-pack-1-available.aspx
You can get the SP1 from here :
After deploying the SP1 the build number you should observe is : 15.00.0847.