MacStadium offers older versions of macOS for customers who want to access that OS on a bare metal hosted Mac.
Our policy is that we offer the hardware and install the OS of the customer's choice from the operating systems available to run on the hardware we host. We have customers with hosted and colocated machines of various operating systems.
Once a customer has accessed a server, it is their responsibility to maintain the software on the device and be aware of the security vulnerabilities related to running older operating systems. We have no way of knowing which OS any one user has installed after release of the server unless we are granted access by the user to troubleshoot or modify the server’s configuration.
Customers running ESXi are able to run any OS under virtualization. We make a reasonable attempt to monitor our network (while maintaining the privacy of our customers) and protect the integrity of said network as its health is of paramount concern to the experience of our customers.
It is the customer’s responsibility to secure their machine in accordance with our Terms of Service. Failure to do so will result in termination of services.
As a company policy, we make a reasonable attempt to keep our customer’s informed of known security vulnerabilities on our blog.