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    DDoS attacks OpenVPN on Pfsense

    Scheduled Pinned Locked Moved Firewalling
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    • GertjanG
      Gertjan @KOM
      last edited by

      @kom said in DDoS attacks OpenVPN on Pfsense:

      Does this happen to anyone else?

      #Metoo.
      Having a static IPv4 your years now, but never saw something like that.
      TLS Keys : of course, I use these.

      No "help me" PM's please. Use the forum, the community will thank you.
      Edit : and where are the logs ??

      1 Reply Last reply Reply Quote 0
      • L
        leungda
        last edited by leungda

        two different sites got attacked. They are different client and network. They got attacked with the same IP address.

        How can i extract OpenVPN log from pfsense

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        • NogBadTheBadN
          NogBadTheBad @leungda
          last edited by

          @leungda

          Whats the IP address, it's not comming from shodan or shadowserver is it ?

          I get these almost every day poking my IPsec VPN, create a blacklist in snort if it is.

          shadowserver:-
          
          216.218.206.0/24
          
          shodan:-
          
          198.20.69.72/29		# census1.shodan.io
          198.20.69.96/29		# census2.shodan.io
          198.20.70.112/29	# census3.shodan.io
          198.20.99.128/29	# census4.shodan.io
          93.120.27.62		# census5.shodan.io
          66.240.236.119		# census6.shodan.io
          71.6.135.131		# census7.shodan.io
          66.240.192.138		# census8.shodan.io
          71.6.167.142		# census9.shodan.io
          82.221.105.6		# census10.shodan.io
          82.221.105.7		# census11.shodan.io
          71.6.165.200		# census12.shodan.io
          188.138.9.50		# atlantic.census.shodan.io
          85.25.103.50		# pacific.census.shodan.io
          85.25.43.94			# rim.census.shodan.io
          71.6.146.185		# pirate.census.shodan.io
          71.6.146.186		# inspire.census.shodan.io
          71.6.158.166		# ninja.census.shodan.io
          198.20.87.96/29		# border.census.shodan.io
          66.240.219.146		# burger.census.shodan.io
          209.126.110.38		# atlantic.dns.shodan.io
          104.236.198.48		# blog.shodan.io
          104.131.0.69		# hello.data.shodan.io
          162.159.244.38		# www.shodan.io
          159.203.176.62		# ny.private.shodan.io
          188.138.1.119		# atlantic249.serverprofi24.com
          80.82.77.33		# sky.census.shodan.io
          80.82.77.139		# dojo.census.shodan.io
          71.6.146.130		# ubtuntu16146130.aspadmin.com
          66.240.205.34		# shodan.io
          216.117.2.180		# malware-hunter.census.shodan.io
          93.174.95.106		# battery.census.shodan.io
          89.248.172.16		# house.census.shodan.io
          185.163.109.66		# goldfish.census.shodan.io
          93.174.95.106		# battery.census.shodan.io
          89.248.167.131		# mason.census.shodan.io
          94.102.49.190		# flower.census.shodan.io
          94.102.49.193		# cloud.census.shodan.io
          185.181.102.18		# turtle.census.shodan.io
          

          Andy

          1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

          1 Reply Last reply Reply Quote 0
          • L
            leungda
            last edited by

            Could you tell me how to create a blacklist in snort?

            1 Reply Last reply Reply Quote 0
            • NogBadTheBadN
              NogBadTheBad
              last edited by

              Create the blacklist file:-

              0_1536609734495_Untitled.jpeg

              Apply it to the interface:-

              0_1536609743860_Untitled 2.jpeg

              You then should see (spp_reputation) packets blacklisted in the blocked list:-

              0_1536609872518_Untitled 3.jpeg

              Andy

              1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

              1 Reply Last reply Reply Quote 0
              • L
                leungda
                last edited by

                Love it. Thanks for your help

                1 Reply Last reply Reply Quote 0
                • KOMK
                  KOM
                  last edited by

                  @netblues said in DDoS attacks OpenVPN on Pfsense:

                  Are you using a static tls key?

                  You have been asked this twice now. It's hard to help you when you don't answer questions.

                  1 Reply Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    You have ZERO need of snort to stop traffic from hitting your wan IP on your openvpn port - ZERO!!!

                    Im with kom - you going to answer the simple TLS key question??

                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                    If you get confused: Listen to the Music Play
                    Please don't Chat/PM me for help, unless mod related
                    SG-4860 24.11 | Lab VMs 2.8, 24.11

                    1 Reply Last reply Reply Quote 0
                    • L
                      leungda
                      last edited by leungda

                      I checked. I didn't use TLS key on OpenVPN setting. Might be you can help me to set this up for extra layer.

                      My OpenVPN set up look like this

                      SSL/TLS + user auth -> DUO -> AD for people to sign in. I am not using local database for user auth

                      Do you sugguest any online guide that I can read of TLS?

                      1 Reply Last reply Reply Quote 0
                      • KOMK
                        KOM
                        last edited by

                        I think you just have to check the Use a TLS key box and then generate new user config that has the TLS key embedded in the .ovpn file, for instance.

                        1 Reply Last reply Reply Quote 0
                        • N
                          netblues
                          last edited by

                          The guide on openvpn hardening has lots of info
                          https://community.openvpn.net/openvpn/wiki/Hardening
                          tls key is described in section Use of --tls-auth
                          As for pfsense, its rather straight forward to implement what it suggests.
                          It also means that you need to send the tls.key to all your clients somehow.
                          Now if you are running clients by the thousands, this is definitely an issue on its own.
                          Imagine this as an initial passphrase. If the client connecting knows it, thserver will deal with him further, spending computing resources to do all the needed security handshakes
                          Obviously it won;t help if you are experiencing a network level attack, ie ping flood saturating your line.

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                          • L
                            leungda
                            last edited by leungda

                            I got the TLS in place at one site. I will keep my eyes on it for the next few days. Also, set up a blocklist on Snort is also a good idea.

                            This guide is quite useful too. Thanks
                            https://community.openvpn.net/openvpn/wiki/Hardening

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