Information
If the interface is not restricted, a VM can detect and be detected by all other VMs with the same option enabled within the same host. This might be the intended behavior, but custom-built software can have unexpected vulnerabilities that might potentially lead to an exploit. Additionally, it is possible for a VM to detect how many other VMs are within the same ESXI system by simply registering the VM. This information might also be used for a potentially malicious objective. By default, the setting is FALSE. The VM can be exposed to other VMs within the same system as long as there is at least one program connected to the VMCI socket interface. THIS CONTROL HAS NO EFFECT IN 5.1. WHETHER SET TO ENABLED OR DISABLED, THE COMMUNICATION IS DISABLED.
Solution
Set vmci0.unrestricted to FALSE in the virtual machine configuration file.