VMware has released vCenter 6.5 Update 1g, vCenter 6.0 Update 3e and vCenter 5.5 Update 3h. These releases fixes a problem with EVC mode problem, when adding new hosts, and some security fixes.
See the full releasen notes for vCenter 6.5 Update 1g here: https://docs.vmware.com/en/VMware-vSphere/6.5/rn/vsphere-vcenter-server-65u1g-release-notes.html
See the full releasen notes for vCenter 6.0 Update 3e here: https://docs.vmware.com/en/VMware-vSphere/6.0/rn/vsphere-vcenter-server-60u3e-release-notes.html
See the full releasen notes for vCenter 5.5 Update 3h here: https://docs.vmware.com/en/VMware-vSphere/5.5/rn/vsphere-vcenter-server-55u3h-release-notes.html