Block telnet access to VPN

[jadeltoro]

Hi.

I have disabled from being able to ping my public IP.

Please, I wanted to know if it would also be possible to not be able to telnet to the public IP and port that I have open for VPN. If not, does this represent a security risk?

Thank you.

[srajeswaran]

I believe you are asking about doing telnet to port 443 (the SSL VPN port) and not the telnet to device (port 23). If you are asking about normal telnet , you can disable the same as suggested in following document - https://docs.fortinet.com/document/fortigate/6.2.0/new-features/46903/telnet-disabled-option

If your question is about telnet to port 443, we cannot disable it. The reason is for Telnet and SSL connection the first packet is a TCP SYN on port 443 and the firewall will respond with SYN-ACK as the service (VPN) is enabled. From the TCP handshake packets the firewall cannot determine if it is telnet or VPN negotiation. It is the case with telnet to any application service.