A few days ago VMware released a public draft of the vSphere 5.0 Hardening Guide. Unlike the vSphere 4.0 Hardening Guide that I’ve talked about before, this version only comes in an Excel Spreadsheet form. Personally, I think the PDF format of the 4.0 Guide is easier to read, but the spreadsheet is good for tracking and sorting of the various parameters. Since the hypervisor is the underpinings of your environment, it is extremely critical that it be secured. A “click next” installation of ESXi, vCenter, network configuration, and VM deployment is just waiting to be compromised.
You can find the vSphere 5.0 Hardening Guide – Public Draft here.