What are the prerequisites for upgrading to CU7

Question

I've been trying to get a definitive list of prerequisites for the upgrade to Exchange 2013 CU7, but every time I find another site with info it says something different.
I know I need to have Domain functional level at 2008 SP1 to run the Schema extension, no problem there. However, I found something that tells me I need to have the Exchange servers running .NET Framework 4.5.2 and Windows Management Framework 4.0, but the
same site then says this is actually needed on the machine used to prepare AD. that means it needs to be one of the domain controllers running these.
Other sites say these need to be installed but do not say which server(s) need them.
Can anyone give me the list of prerequisites? The information I managed to find on the Microsoft site mentioned nothing about the domain functional level, I only found this requirement after trying to run the schema extension and getting a report the DFL
needs to be 2003 native mode or above, I ran a targeted search for DFL requirements and found a table listing this for different versions of Exchange.
This is frustrating to say the least, makes carrier pigeons seem a viable alternative right now!

Answer 1

Thanks to everyone who has replied, but the fact 3 different people have replied and given varying replies is what I was talking about.
Microsoft, in the prerequisites information found at
https://technet.microsoft.com/library/bb691354(v=exchg.150).aspx say this
Active Directory preparation
The computer you want to use to prepare Active Directory for Exchange 2013 has specific prerequisites that must be met.
Install the following software, in the order shown, on the computer that will be used to prepare Active Directory:
The version of Microsoft .NET Framework that corresponds to the version of Exchange 2013 you're installing.
Exchange CU7 and later   .NET Framework 4.5.2
Exchange CU6 and earlier   .NET Framework 4.5.1
The version of Windows Management Framework that corresponds to the version of Exchange 2013 you're installing.
Exchange 2013 SP1 or later   Windows Management Framework 4.0
Exchange 2013 CU3   Windows Management Framework 3.0
but from what others say, installing .NET 4.5.2 before installing CU7 will break Exchange services.
I think I'm just going to try the schema extension without installing anything and see what happens, if I still have my job after this I will let you know