easy

Level 3: Server Fingerprinting (No Server Header)

Recon

Challenge

Your input is reflected in a results page without proper output encoding. Use this to execute JavaScript.

What you'll learn
  • Why output encoding is essential.
  • Safe demonstration of XSS via sandboxed iframe.
Need a Hint?
Try using a <script> tag or an onerror handler on an image.
Reflected Result (sandboxed):
Vulnerable pattern
// Reflected into HTML without encoding
<div><?= $_GET['q'] ?></div>