Question 260
An enterprise access-control incident describes: A captive portal advertises an IP address that does not match its public certificate, and mobile clients display a certificate identity warning before login. What validation should be repeated before subsequent rollouts?
Explanation
Correct Answer
Track portal certificate expiration and FQDN changes in guest-service maintenance. This control addresses recurrence of the observed failure. The governing behavior is: Portal trust depends on certificate hostname and chain validation; successful RADIUS redirection alone does not make the HTTPS identity trusted. The ongoing acceptance check remains: A pilot guest loads the portal without a TLS name mismatch and cannot be redirected to an untrusted duplicate endpoint.
Incorrect Answers
Successful portal credential validation does not itself change an already authorized NAD session without the required update mechanism. The repeat risk here is different: Portal trust depends on certificate hostname and chain validation; successful RADIUS redirection alone does not make the HTTPS identity trusted. A directly relevant preventive control is: Track portal certificate expiration and FQDN changes in guest-service maintenance.
Allow only the portal's approved HTTPS destination and essential DNS or DHCP bootstrap traffic in the limited-access redirect ACL. The repeat risk here is different: Portal trust depends on certificate hostname and chain validation; successful RADIUS redirection alone does not make the HTTPS identity trusted. A directly relevant preventive control is: Track portal certificate expiration and FQDN changes in guest-service maintenance.
A hotspot's acceptance step does not prove a sponsor approved a named visitor or checked their eligibility. The repeat risk here is different: Portal trust depends on certificate hostname and chain validation; successful RADIUS redirection alone does not make the HTTPS identity trusted. A directly relevant preventive control is: Track portal certificate expiration and FQDN changes in guest-service maintenance.