VMware vSphere environments are sometimes deployed using the default configuration of many features and services and they are not regularly checked for potential improvements in terms of VMware security standards and best practices.
VMware regularly updates its hardening guides available at https://www.vmware.com/security/hardening-guides.html which provides essential information and recommendations on how to make the vSphere infrastructure more secure.
We have tried to pinpoint several of the most essential aspects of the vSphere infrastructure hardening in the following sections.