1. Web Security Academy
  2. Prototype pollution
  3. Client-side vulnerabilities
  4. Lab

Lab: DOM XSS via client-side prototype pollution

PRACTITIONER

This lab is vulnerable to DOM XSS via client-side prototype pollution. To solve the lab:

  1. Find a source that you can use to add arbitrary properties to the global Object.prototype.

  2. Identify a gadget property that allows you to execute arbitrary JavaScript.

  3. Combine these to call alert().

You can solve this lab manually in your browser, or use DOM Invader to help you.

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