HexBrain

Cloudflare Public Bug Bounty · Report #3423950

[Variation of #3321406] YetAnother 1-Click Chaining of Self-XSS, Cookie Tossing and AntiCSRF Token Prediction leads to auto approval in AccessTempAuth

Validstatus
highseverity
63upvotes
14 Apr 2026disclosed

Summary

We have resolved an issue in Cloudflare Access where an exploit chain involving the Browser Isolation email field could allow for unauthorized approvals within the Temporary Auth workflow. This has been fully remediated, and we thank the researcher for their help in hardening our authentication flows

Detailed Writeup: https://kazama.in/self-xss-to-cloudflare-single-click-approvals/

How it was found

The write-up for this report has not been downloaded yet, or the program disclosed it without one. Read it on HackerOne.

This report was disclosed publicly on HackerOne and belongs to its author and the program. See the original