Most users are unaware of protocols and security. Even if your websites offer secure services, users generally still try to access websites using HTTP.
As a result, it's best to provide at least an HTTP service that redirects requests to HTTPS. Even then, if a Man-in-the-Middle (MITM) attacker or CRL causes a certificate validation error, many users will incorrectly assume it is harmless, and click through the alert dialog to access the website anyway—sometimes called “click-through insecurity.” The resulting unsecured connection exposes sensitive data and their login credentials.
Newer versions of major browsers such as Mozilla Firefox and Google Chrome have a built-in list of frequently attacked websites such as gmail.com and twitter.com. The browser will only allow them to be accessed via HTTPS. This prevents users from ever accidentally exposing sensitive data via clear text HTTP. Additionally, the browser will not show click-through certificate validation error dialogs to the user, preventing them from ignoring and bypassing fatal security errors.
Similarly, you can also force clients to use only HTTPS when connecting to your websites. To do this, when FortiWeb is performing SSL/TLS offloading, configure it include the RFC 6797 (http://tools.ietf.org/html/rfc6797) strict transport security header. All compliant clients will require access to that domain name via a connection using HTTPS.
- If you want to redirect clients that initially attempt to use HTTP, configure an HTTP-to-HTTPS redirect. See Example: HTTP-to-HTTPS redirect and Rewriting & redirecting.
- When configuring the server policy, enable Add HSTS Header and configure Max. Age.