So according to the answer to the question above it is possible that when one website on a server is vulnerable to remote execution it implies that all websites hosted on the same server could possibly be compromised.
Therefore I was wondering if one would create a website with this vulnerability on purpose. Then let it be hosted by a hosting provider. Such a hosting provider probably has somewhere around 50 websites hosted on one server.
Could this lead to compromise of all the other websites on this server? If no, how is this prevented? If yes, how could one prevent this?
Discussion on this question has lead to a new question regarding prevention of this thread: How do hosting providers prevent the compromise of one website from causing the compromise of another one?