Re: Captive Portal redirection fails in Google Chrome
If that wifi let you through, but shouldn't, then it's a misconfiguration of identity-based firewall policies IMHO.
Flow debug or logs for your source IP might help you to figure out which policy you are passing through and fix that if needed. Maybe there is some SSO or worst, some non-identity based policy which let you through unauthenticated unintentionally.
Tom xSilver, planet Earth, over and out!