Be sure to read the download page and the readme file (English only).
This Service Pack can be applied to AutoCAD 2015 and AutoCAD LT 2015 installed as a standalone application as well as AutoCAD 2015 and AutoCAD LT 2015 installed from the following suites or bundled products.
AutoCAD Civil 3D 2013 Service Pack 1 is now available for download! This Service Pack includes all previous hotfixes for AutoCAD Civil 3D 2013. It also includes the fixes included in AutoCAD 2013 Service Pack 1.1 and AutoCAD Map 3D 2013 Service Pack 1.
Thank you Autodesk! I have not installed it yet, but I'm looking forward to this fix -> "In drawings with a custom UCS, switching from the model tab to the layout tab will no longer reset model tab to isometric."