Microsoft Dynamics Ax 2012 R2 CU8 is now available to our customers for download on LCS, Customer and Partner source. Cumulative Update 8 build number is 6.2.2000.14. You must have Microsoft Dynamics AX 2012 R2 installed or Microsoft Dynamics AX 2012 R2 to apply this cumulative update. For installation instructions, download the Installation guide for cumulative update 8 for Microsoft Dynamics AX 2012 R2
The release notes is another great place to start with Cumulative Update 8 for Microsoft Dynamics Ax 2012 R2 deployment.
To learn about known issues in cumulative update 8, log into LCS by using CustomerSource or PartnerSource account. Then, in the Issue search box, enter "CU8 known issue" as the query for Microsoft Dynamics AX 2012 R2.