The 0 XSS Bounty: A Deep Dive into Reflected Cross-Site Scripting (XSS) Exploitation

By /

Listen to this Post

Featured Image

Introduction:

Reflected Cross-Site Scripting (XSS) remains one of the most common web vulnerabilities, allowing attackers to inject malicious scripts into web pages viewed by unsuspecting users. In this article, we dissect a real-world XSS bug bounty case where a security researcher discovered a flaw with a minimal payout—highlighting the challenges and automation techniques in modern bug hunting.

Learning Objectives:

  • Understand how reflected XSS vulnerabilities work.
  • Learn how to craft and test XSS payloads.
  • Explore automation strategies for efficient bug hunting.

1. Understanding Reflected XSS

Reflected XSS occurs when user input is immediately returned by the web application without proper sanitization, allowing script execution in a victim’s browser.

Payload Used:

%3C/script%3E%3Cscript%3Ealert(111)%3C/script%3E

Decoded:

</script><script>alert(111)</script>

How It Works:

  1. The payload is injected into a vulnerable input field or URL parameter.
  2. The server reflects the input back in the response without escaping.
  3. The browser interprets the `