: A simple login page where you usually have a username but no password.
Authenticate every request that needs elevated privileges. For APIs, this means using , OAuth2 flows , or mutual TLS . For web applications, rely on the standard session cookie tied to a logged‑in user with known roles. x-dev-access yes
x-dev-access yes ✅ Dev mode: activated. Let’s break things (so we can fix them better). : A simple login page where you usually
To exploit this, you must manually inject the header into your request to the server. There are two primary ways to do this: 1. Using Browser Developer Tools For web applications, rely on the standard session
For example, an Nginx ingress configuration can explicitly invalidate the header:
: Attackers analyze client-side JavaScript, web manifests, public GitHub repositories, or hidden comments in HTML. In many real-world scenarios and CTF exercises, developers leave hints in the code (e.g., a commented-out line like // fetch('/api', headers: 'X-Dev-Access': 'yes') ).
Below is a blog post write-up detailing how to exploit this vulnerability.