Today I read about ransomware called Erebus that supposedly targets Linux servers and encrypts all the data there. What I can't find is any reference to the details of this type of attack, i.e. how the system's security was breached and privilege escalation was performed. Was it a user error? Was it just bad system security (i.e. lack of updates or vulnerable configuration)? I can't find anything about this.
I would guess any decent sysadmin at least puts every Web server in a chroot jail or better, a Container or VM, which aren't watertight, but a lot harder to break out of in any case. Am I being idealistic?