Forum Thread: Enumeration, Help Me Please.

I am conducting a simple exercise against a server and a client (both outside my network, and both are remote).

The server is a node.js app with a code like this: pastebin.com/zVqQ5f13

The client can be written in any language, as long as it is passing JSON objects.

What I Want?
-> intercept (and modify) all incoming JSON objects for the server.

My Plans:
-> MitM = should have been perfect but not possible outside the network.
-> BGP hijacking = not possible because of the lack of resources.
-> Hijack the server's router = I don't know if this was done before, I don't even think it's possible.

-> Install a backdoor on server = I can't find any vulnerability on the server's source code, I don't know if this is possible

Server Specs:
->as far as I know they are all linux

Please what else do I miss