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    Suspicious Traffic?

    Scheduled Pinned Locked Moved General pfSense Questions
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    • D
      deanfourie @johnpoz
      last edited by

      @johnpoz Heres what I found in the states table.

      Capture.PNG

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      • johnpozJ
        johnpoz LAYER 8 Global Moderator @deanfourie
        last edited by

        @deanfourie Dude stop having ntop try to discovery your wan.

        An intelligent man is sometimes forced to be drunk to spend time with his fools
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        • D
          deanfourie @johnpoz
          last edited by

          @johnpoz oh that's not ntop that's the states table.

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator @deanfourie
            last edited by johnpoz

            @deanfourie Again the only thing that would do what your seeing is ntop in discovery mode.. Turn it off and that traffic will stop..

            Its not suspicious traffic - its ntop in discovery mode..

            Why you would have it trying to discover your wan what is causing that traffic.

            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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            • D
              deanfourie @johnpoz
              last edited by

              @johnpoz so you're telling me that ntop is creating these outbound ssh connections?

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator @deanfourie
                last edited by johnpoz

                @deanfourie Yes - its discovery mode.. Is looking for stuff.. ssh (port 22) being one of the things it looks for.

                Here is a recent thread - same sort of thing

                https://forum.netgate.com/topic/172680/ntopng-sshguard

                Here is the code from the ntop

                https://github.com/ntop/ntopng/blob/dev/scripts/lua/modules/discover_utils.lua#L495

                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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                • D
                  deanfourie @johnpoz
                  last edited by

                  @johnpoz but would it not see this traffic only if this traffic existed? Hence why it's seeing it

                  I don't know what am I missing?

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @deanfourie
                    last edited by johnpoz

                    @deanfourie its creating it!! Turn off discovery!

                    discovery.jpg

                    Ntop is creating the traffic - so yes you see it

                    Or uncheck ntop from using your wan.. There is little reason for ntop on your wan. You wan to see where your clients are going - not all the noise hitting your wan.

                    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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                    • D
                      deanfourie @deanfourie
                      last edited by

                      @deanfourie dude, my WAN is a upstream gateway, is is simply another private network as far as ntop is concerned.

                      The fact is I'm seeing SSH traffic from my pfSense WAN interface, and seeing the connections in the pfSense states table.

                      How's that normal?

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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Because ntop is sending them to try to detect hosts on that subnet. That's what the active discovery does.

                        D 1 Reply Last reply Reply Quote 1
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @deanfourie
                          last edited by

                          @deanfourie I have no idea what else to tell you - ntop is creating that traffic, its not suspicious.

                          If you don't want it doing it, then turn it off from doing it, if you want your ntop discovery your isp network - have at it, they might not be happy about that, or your isp other users, etc..

                          Why don't you turn off the auto discovery I showed you - do you continue to see this traffic?

                          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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                          • D
                            deanfourie @stephenw10
                            last edited by

                            @stephenw10 but the connection is to a external IP?

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

                              @deanfourie said in Suspicious Traffic?:

                              but the connection is to a external IP?

                              What are you not understanding that network is trying to be discovered by ntop - its your actual ISP network.. Doesn't matter if your behind a double nat or not.

                              Again turn off the auto discovery - does that traffic go away?

                              pfsense out of the box would not be creating random connections to IPs out on the internet. But you know what would - ntop discovery.. You are running ntop, I showed you from sniff clearly showing ntop doing discovery - see the user agent in what I posted..

                              So either let it do what its doing, or disable auto discovery, or configure ntop not to use your wan interface on pfsense for discovery.

                              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
                              • D
                                deanfourie @johnpoz
                                last edited by

                                @johnpoz ok, ive turned of network discovery (active network discovery) and it has not gone away. Still there are multiple SSH sessions to a random WAN IP

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                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator @deanfourie
                                  last edited by johnpoz

                                  @deanfourie said in Suspicious Traffic?:

                                  Still there are multiple SSH sessions to a random WAN IP

                                  Your still seeing them being created, or they are old ones in your state table..

                                  Here is the thing there is NOTHING in pfsense that would do that - NOTHING.. So its ntop doing it, or you have some other package installed doing it. Pfsense does not just randomly create outbound connections on 22 to IPs on your isp network. It doesn't - Period!

                                  You looked in your state table, so its not some client behind pfsense doing it, or you would see the client ip in the state table that is trying to do it..

                                  edit: Also I don't think turning it off instantly stops and current discovery that is running.. If you have it on there would be discovery time, defaults to every 15 minutes I believe.

                                  Turn off ntop completely - do you still see new connections being made?

                                  If you wan to see what is making the connections from pfsense, do a sockstat, here in a session on pfsense I created a ssh connection to one of my box on my network. Then viewing sockstat I can see that connection being made with ssh program.. If your still see them after you have stopped ntop and kill all existing states..

                                  sockstat.jpg

                                  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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                                  • D
                                    deanfourie @johnpoz
                                    last edited by

                                    @johnpoz ok ill go through and disable all my packages one by one

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                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator @deanfourie
                                      last edited by johnpoz

                                      @deanfourie see my edit in finding what is creating the connections using sockstat

                                      But I would bet a very large sum of money its ntop.. A very large sum!

                                      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
                                      • D
                                        deanfourie @johnpoz
                                        last edited by

                                        @johnpoz Yea, you are correct. It is ntop.

                                        But I still dont understand why.

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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator @deanfourie
                                          last edited by

                                          @deanfourie because that is what it does with discovery - it finds an IP, and then tries to discover what it is, what os its running, etc.. I showed you the code in the discovery part of ntop where it does a ssh probe.

                                          Here I just turned it on for my wan.. And bam it created ssh to IPs it discoverd..

                                          discovery.jpg

                                          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
                                          • D
                                            deanfourie @johnpoz
                                            last edited by

                                            @johnpoz Thats so strange, why SSH?

                                            So it only happens with network discovery?

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