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    Concerned port scan of pfSense public WAN IP shows all ports open (most likely noob error)

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    • D
      dmtdva
      last edited by

      Firewall rules (WAN):

      Rules (Drag to Change Order)
      States Protocol Source Port Destination Port Gateway Queue Schedule Description Actions
      0 /2 KiB
      * Reserved
      Not assigned by IANA * * * * * Block bogon networks
      0 /0 B
      IPv4 UDP * * WAN address 1194 (OpenVPN) * none OpenVPN OpenVPN wizard

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      • D
        dmtdva
        last edited by dmtdva

        Port scan (from 4G device scanning public IP of pfSense WAN interface):

        Host is up (0.039s latency).

        PORT STATE SERVICE
        1/tcp open tcpmux
        3/tcp open compressnet
        4/tcp open unknown
        6/tcp open unknown
        7/tcp open echo
        9/tcp open discard

        ... for every port! :-S

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        • RicoR
          Rico LAYER 8 Rebel Alliance
          last edited by

          Tell us more about your Setup, show Firewall Rules and Logs as Screenshots.
          I just checked with a very basic 2.4.4-p3 setup and it behaves exactly as expected.
          pfSense_Basic_WAN-Rules.png

          nmap -sT xxx.xxx.xxx.141
          
          Starting Nmap 7.60 ( https://nmap.org ) at 2019-06-02 10:35
          Nmap scan report for xxx.xxx.xxx.141
          Host is up (0.0050s latency).
          All 1000 scanned ports on xxx.xxx.xxx.141 are filtered
          
          Nmap done: 1 IP address (1 host up) scanned in 49.80 seconds
          

          pfSense_Firewall2.png

          Make sure the Virgin modem isn't the devices answering to this request.

          -Rico

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          • D
            dmtdva
            last edited by dmtdva

            Hi thanks for reply.

            Wanrules.JPG FirewallLogs.JPG

            Many of the log entries are seemingly denying external IP#s from accessing 23, 8080 etc

            Perhaps it is just my Virgin Media router that is blocking the requests?

            I cannot think how to test this easily.

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

              Lets say the port X was actually open... If you don't have it something listening, it could not show open.. There is nothing sending back a syn,ack to the syn... So whatever you testing methodology is wrong.. Is your phone on IPv6 - many carriers only give their mobile devices IPv6 and send that traffic through a gateway to get to IPv4.. Maybe they run you through a proxy?

              If you want to do an external scan - then go to one of the services that do it for free.. Shields Up is a pop one.. And will give you the so called stealth info <rolleyes>..

              Or validate your external source is not running through some sort of "ISP" shenanigans.

              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

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

                @dmtdva

                Why is the automatic block RFC 1918 rule missing?

                Do you actually have two routers or is the Virgin one in modem mode?

                Andy

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

                D 1 Reply Last reply Reply Quote 0
                • GertjanG
                  Gertjan
                  last edited by

                  Use this can test https://www.grc.com/x/ne.dll?rh1dkyd2

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

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                  • D
                    dmtdva @johnpoz
                    last edited by

                    @johnpoz This is the result of the third party scan, which as you have mentioned might be a better method than a phone ISP. No open ports at least, which is reassuring! Thanks to all who helpd with your time.

                    Still wandering why they are showing as stealthed and not closed however.

                    Scan.JPG

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                    • D
                      dmtdva @NogBadTheBad
                      last edited by dmtdva

                      @NogBadTheBad I purposefully removed that as one client used AWS Route 53 entries to point back to local addresses and this prevented it.

                      Just the Virgin one so....

                      Virgin Superhub (Modem mode) --> RJ45 VLAN 0.80 switch untagged through to trunk port on --> ESXi --> ESXi trunk port through to pfSense VM on vmx.080

                      The VLan part is seemingly working fine.

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by johnpoz

                        Stealth means there was no answer, closed means that something was returned.. either a RST or icmp redirect, etc.

                        Normally a firewall would just drop and not return anything.. ie "stealth" which is misleading at best. Just because your scan doesn't return anything doesn't actually mean you can not be found, etc..

                        Those are 135, 137-139 that are returning "closed" Could be your isp telling you sorry No Go on those ports.. Many an isp will on purpose block those.

                        Ah and the other is 445, yeah that is smb over tcp.. Also normally blocked by many a isp.

                        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

                        D 1 Reply Last reply Reply Quote 1
                        • D
                          dmtdva @johnpoz
                          last edited by johnpoz

                          @johnpoz Thanks mate. That makes sense, guessing the root cause was me testing over a 4G/cellular data connection and therefore getting unreliable results.

                          Still have the results here:

                          ost is up (0.039s latency).

                          PORT STATE SERVICE
                          1/tcp open tcpmux
                          3/tcp open compressnet
                          4/tcp open unknown
                          6/tcp open unknown
                          7/tcp open echo
                          9/tcp open discard
                          13/tcp open daytime
                          17/tcp open qotd
                          19/tcp open chargen
                          20/tcp open ftp-data
                          21/tcp open ftp
                          22/tcp open ssh
                          23/tcp open telnet
                          24/tcp open priv-mail
                          <snipped by mod - just make post so long and useless info>
                          Won't let me move into code - says spam ;)

                          Youd think they would set every port to closed if they were trying to stop hackers unless they have something akin to a honeypot.

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by johnpoz

                            Not sure what shenanigans they could be up too.. Could be something to do with a ipv6 to ipv4 gateway, they could be running you through some sort of tcp proxy, etc.

                            But tell you for sure testing such stuff over cell can be misleading info..

                            Could be a form of optimization.. where their handing you back a syn,ack before any sort of connection is actually made, etc. etc..

                            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

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