What security does nginx provide between server blocks?
Here is an example scenario. Say I have two server blocks configured with nginx. Each serves up a web application to authenticated users. I am worried that if one web application is compromised that it could be leveraged to gain access to the other web application.
For example, say one web application has a remote file inclusion vulnerability which allows the attacker to get a shell. That shell would have the privileges of the web server (www-data). With those privileges, the attacker could start reading files from the other web application, right?
Is there any additional separation one could configure into nginx server blocks for added security in this scenario?