HTTP 502 with scan http enabled on VPN connections only

Hello,

While remotely connected, I encounter an issue browsing internal resources on port 80 and 80 only. I receive an HTTP error 502 and this happen when the firewall rule for the VPN connection has the "Scan HTTP" option activated. If the option is disabled OR if I browse the same resource configured on another port (8181 for instance) if works perfectly.

Any idea ?

Thank you