Contains my solution for the DTF project for the course Network Security HS 2021 at ETH Zurich.

In this project, you are given a virtual machine and are supposed to analyze and implement common security measures you have seen in this course. Your task is to create a program which fixes all of these issues automatically. We assume some enough familiarity with Linux systems[^1] to navigate the shell and execute basic commands.

Below you are given a list of tasks, either consisting of problems or issues with the current setup. Some of these might not be resolvable before you solved related problems, it is up to you to figure out these depedencies yourself.

You are permitted (and even encouraged) to install new packages on the machine, inspect and change configuration files, and so on. See the "Tips" section for some helpful hints.

Your solution repository is automatically cloned into your student's home directory for your convenience.

The VM has issues reaching the internet. Find out why this is the case and resolve the issue.

Tip: Try pinging the VM from your end. What do you see? Why might that happen?

Your VM is running a "database server" which is listening for TCP connections on port 5432. Ensure that only the grading server running at grader.dtf.netsec.inf.ethz.ch is able to access the database server from the internet.

There have been reports that malicious actors exfiltrated secure passwords from your VM via HTTP. Find out how this happened and fix it.

Your VM is running the well known and widely deployed nginx webserver, you can use systemctl status nginx to view its status.

Currently the VM serves HTTPS traffic using a self-signed certificate. From the course you recall that while the data exchanged is still encrypted, a proper chain of trust would be preferable. The first project dealt with you implementing a client for the ACME protocol, while this one requires you to use an ACME client to acquire a TLS certificate.

The ACME directory from which you should order the certificate is located at acme.dtf.netsec.inf.ethz.ch. The ACME server directory is at /acme/default/directory. Your task is to request a certificates for the domain name nethz.student.dtf.netsec.inf.ethz.ch where nethz is your ETH username and configure TLS traffic in the nginx web server.

This domain only resolves internally, do not worry if you can't see the DNS records from your client machine.

Inspect the webserver's TLS configuration. Is it secure? If not fix the identified issues and make it secure.