Blocking softether VPN connection


  • Hi all,

    Any way to block softether VPN connection? I have block most of the ports in my firewall except 80, 8080, ftp, email, DNS, ntp ports, somehow softether VPN can still connect to the server to bypass the firewall rules.


  • Some VPN services tunnel over 443 so those are hard to block without killing web access entirely.  From their site:

    Penetrates Firewall by SSL-VPN
    Are you having trouble with IPsec-based legacy VPN products? Replace it to SoftEther VPN. SoftEther VPN Protocol is based on HTTPS so almost all kinds of firewalls will permits SoftEther VPN's packets.

    Your only option now is to block their access points.


  • @KOM:

    Some VPN services tunnel over 443 so those are hard to block without killing web access entirely.  From their site:

    Penetrates Firewall by SSL-VPN
    Are you having trouble with IPsec-based legacy VPN products? Replace it to SoftEther VPN. SoftEther VPN Protocol is based on HTTPS so almost all kinds of firewalls will permits SoftEther VPN's packets.

    Your only option now is to block their access points.

    Thanks for your reply, I think is a bit hard to block for now as we require port 443


  • Only way is snort/layer7 if the app identify itself but doubtful the main was is to have a proxy server with ssl introspection.

  • LAYER 8 Global Moderator

    Yeah its getting really hard to block this sort of thing.. So while you don't actually have to decode the traffic to see that openvpn traffic is not actually normall ssl traffic.  You can run it inside an actual ssl tunnel, etc.  I am not sure what softethers ssl vpn looks like, maybe its just like a stunnel?  And impossible to detect without mitm of the ssl connection.

    But for sure its an uphill battle trying to block such traffic.  Especially when they run over ports that you Need to talk to the internet at all like 443..


  • I am blocking using IP address in firewall rules and squid guard.

    but there is a long list of ip address of the vpn server based on the vpngate website