Critical Thinking - Bug Bounty Podcast

Episode 111: How to Bypass DOMPurify in Bug Bounty with Kevin Mizu

Feb 20, 2025

Kevin Mizu, a security researcher at Bisecure specializing in web app security, discusses the critical vulnerabilities associated with DOMPurify. He explores dangerous allow-lists, improper sanitization techniques, and the significance of managing configurations. Mizu shares insights into his own bug bounty experiences, including the exploitation of misconfigured regex patterns and the nuances of Unicode normalization. The conversations emphasize creative thinking in cybersecurity and the intricate methods used to bypass HTML sanitization, underscoring the complexities in maintaining web application security.

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Unraveling Web Vulnerabilities

01:56 • 11min

Exploring DOM Purify: Risks and Configurations

Exploiting DOMPurify Vulnerabilities

22:15 • 13min

Unpacking DOM Manipulation and Event Delegation

Regex Vulnerabilities in Web Security

Understanding DOMPurify Challenges in Web Security

44:00 • 11min

Bypassing DOMPurify: Vulnerabilities and Exploits

55:23 • 17min

Vulnerabilities in DOMPurify Sanitization

01:12:28 • 11min

Creativity and Risks in Bug Bounty Hunting

01:23:50 • 3min

Exploring Unicode Normalization for Bypassing Security Measures

01:26:36 • 3min

Sanitization Vulnerabilities and DOMPurify Exploits

01:29:21 • 16min

Exploring JavaScript Execution Vulnerabilities in DOMPurify and Happy DOM

01:45:10 • 2min

Exploring Vulnerabilities in DOMPurify and JavaScript Evaluations

01:46:53 • 2min