Troubleshooting: 403 Error After Entering a Username on a CORS-Enabled Realm

Version Affected: All
 
 

Overview

On a realm with CORS (Cross-Origin Resource Sharing) enabled, the realm loads fine, but after the user types their username, they see a 403 error instead of the multifactor methods page. Reloading the page (for example, clicking the address bar and pressing Enter) successfully loads the MFA page.

Cause

CORS is configured for the realm with failUnlistedOrigins="true", and the origin making the request isn't in the realm's list of allowed origins -- so CORS throws a 403.

Resolution:

Use the browser's developer tools to find the actual origin being blocked when the 403 occurs -- it's often the address of the SecureAuth server itself, for example https://sa.example.com. Add a CORS entry to the realm's web.config for that origin:

<cors enabled="true" failUnlistedOrigins="true">
    <add origin="https://sa.example.com" />
</cors>

Save the file -- IIS picks up the change automatically.


 

SecureAuth Knowledge Base Articles provide information based on specific use cases and may not apply to all appliances or configurations. Be advised that these instructions could cause harm to the environment if not followed correctly or if they do not apply to the current use case.

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