Episode 169: Attacking OAuth 2.1

Episode 169: In this episode of Critical Thinking - Bug Bounty Podcast gr3pme goes over some of the changes from OAuth 2.0 vs 2.1 and how Hackers can capitalize.

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Shoutout to YTCracker for the awesome intro music!

====== Links ======

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https://x.com/rez0__

https://x.com/gr3pme

Critical Research Lab:

https://lab.ctbb.show/ 

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====== This Week in Bug Bounty ======

Intigriti is providing free Burp Pro for Hackers!

https://www.intigriti.com/blog/news/intigriti-collaborates-with-portswigger-to-support-ethical-hacking-excellence

====== Resources ======

Django-allauth Account Takeover (ZeroPath Audit)

https://zeropath.com/blog/django-allauth-account-takeover-vulnerabilities

CVE-2025-4144: Cloudflare Workers PKCE Bypass

https://github.com/cloudflare/workers-oauth-provider/security/advisories/GHSA-qgp8-v765-qxx9

CVE-2025-54576: OAuth2-Proxy Auth Bypass

https://zeropath.com/blog/cve-2025-54576-oauth2-proxy-auth-bypass

====== Timestamps ======

(00:00:00) Introduction

(00:02:16) OAuth 2.0 Standards

(00:12:08) Agent to Agent Communication

(00:17:19) CVE Case studies