I suspect they meant 4.8 Patch 1, which is the minimum required version for 2012 R2 / 8.1.
However, Patch 2 is out, which fixes the OS version reporting for Windows Server 2012 R2 / 8.1.
Go to the McAfee download site armed with your grant number, and get MA480P2WIN.zip (agent build 220.127.116.110) from the McAfee Agent section
Works fine on our 2012 R2 servers.
And while you're there, get the Virusscan 8.8 Patch 4 full repost, if you haven't already. That's needed for 2012 R2 as well.