FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
Vbharath_FTNT
Article Id 190163

Description

 
This article explains how to disable HTTPS replacement messages for explicit proxy traffic.


Solution

 
Disabling HTTPS replacement messages is helpful to avoid certificate errors when an HTTPS website is blocked by the FortiGuard Web filter/URL filter.

This setting is useful when SSL deep inspection is not used on the FortiGate unit to avoid certificate errors while accessing HTTPS websites.

Without SSL Deep scan, FortiGuard Web filter/URL filter can extract the hostname from the CN field in the certificate or the SNI extension in TLS extended client hello to rate the websites.

Note then when the replacement message is disabled, the user will not get any message on the browser when access to the website is blocked.

Configuration CLI:
 
config web-proxy explicit
    set https-replacement-message disable
end