This article explains an error that occurs when testing Auth Challenge Captcha with Advanced Customizations for Universal Login (ACUL). This issue arises when attempting to use site keys from Cloudflare Testing while following the implementation steps in Implementing CAPTCHA using ACUL. When entering an email address on the login prompt, the following error message appears:

Select the checkbox to verify you are not a robot.

This error is visible even when testing the invisible widget. A 400 Bad Request error is also observed in the HTTP Archive (HAR) file.

• Auth Challenge Captcha

• Advanced Customizations for Universal Login (ACUL)

Auth0 does not currently support the use of customer-provided site keys for Auth Challenge. The system requires the default configuration, and manually inputting Cloudflare site keys in the code results in the validation error.

Submit a feature request if this functionality is desired.