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    GRC closed instead of stealth ports?

    Scheduled Pinned Locked Moved Firewalling
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @mjgtp
      last edited by johnpoz

      Exactly - if you do not see that port that they are showing closed hitting your wan, but its showing closed on the scanner - then something between you and them did something that shows that port closed, like sent a rst is the only way, or it answered with a syn,ack - which should show it as open then, etc.

      As you see in my scan - those ports 135 for example never get to pfsense.. Nothing in the path sends anything back on those, but they never get to me. Blocked somewhere between them and me. Like I said many isp block those ports on purpose..

      Could be your isp changed how they block those ports, or device pfsense is connected to is sending them? Or something else between you and them..

      Really the only way you could see something like that if the traffic was actually getting to pfsense is you have that port forwarded to something internally that is sending back a rst.

      BTW - Reject on a wan facing interface is a horrible horrible idea.. Like I said you could do it on pfsense - but its not something you should ever do by mistake or accident. And not something you should ever really do ;)

      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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      • JKnottJ
        JKnott @johnpoz
        last edited by

        @johnpoz said in GRC closed instead of stealth ports?:

        But pfsense wouldn't send a reject. Now if they were actually forwarded through and could get to that something - it might send a reject.

        Wouldn't pfsense send a reject, if that was selected? The choices are "block" which does not respond at all and "reject" which sends a reject.

        From the manual:

        A packet matching this rule will be discarded and for supported protocols, a message will be sent back to the originator indicating that the connection was refused.

        I use block on the WAN interface so that an attacker would waste time waiting for a reponse and reject internally to end the attempt as quickly as possible.

        However, in this case above, there is no reject on the WAN interface.

        PfSense running on Qotom mini PC
        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
        UniFi AC-Lite access point

        I haven't lost my mind. It's around here...somewhere...

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

          It wouldn't via the rules he has shown was my point. As I said it would have to be a specific reject..

          You would have to specific do that - and even the floating rule he has as reject couldn't do it - its to all ports.. So if that was doing it - all the ports would be coming back closed. And its not set for wan anyway, and how would his own wan be in that pb alias? 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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          • Bob.DigB
            Bob.Dig LAYER 8
            last edited by Bob.Dig

            My old shitty cable-ISP used to do this, after maybe 60 days or so, I got this. I then had to manually reconnect and it was gone again and I had my open ports back.

            1590336789482-capturetccqkp0.png

            Somehow it is still fascinating to me to look at. ๐Ÿ˜ฒ

            johnpozJ 1 Reply Last reply Reply Quote 0
            • M
              mjgtp
              last edited by

              Ok, finally got this figured out. It was my gateway that was rejecting the requests. After a hard reset, it switched over to blocking, but the gateway was still the one doing the work, so had to put it in DMZ+ mode so I could get traffic on the PfSense box. I'm seeing the individual port requests now via the packet capture and they're ALL showing as stealth. Woot!

              Thanks all for your help!

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator @Bob.Dig
                last edited by johnpoz

                @bob-dig ha that is odd graph to be sure.. WTF?? BTW, I take it that is some old IP, so no concern with posting that public IP?

                @mjgtp glad you got it sorted.

                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

                Bob.DigB 1 Reply Last reply Reply Quote 0
                • Bob.DigB
                  Bob.Dig LAYER 8 @johnpoz
                  last edited by Bob.Dig

                  @johnpoz I never had a static IP with any ISP around here. And I even do things that those dynamic IPs change more often. ๐Ÿ•ต

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

                    I don't have static, and my IP hasn't changed in 2 some years.. Why would it ever change? It just keeps renewing the same lease, because my device is on 24/7/365.. I am glad it doesn't change to be honest..

                    Some people have an aversion to posting their public IP is all.. If your ok with it..

                    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

                    Bob.DigB JKnottJ 2 Replies Last reply Reply Quote 0
                    • Bob.DigB
                      Bob.Dig LAYER 8 @johnpoz
                      last edited by Bob.Dig

                      @johnpoz said in GRC closed instead of stealth ports?:

                      If your ok with it..

                      I am ok with it, I have another one every morning. ๐Ÿ˜
                      Also I am not with that ISP anymore, thanks god.

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                      • JKnottJ
                        JKnott @johnpoz
                        last edited by

                        @johnpoz said in GRC closed instead of stealth ports?:

                        Why would it ever change?

                        I think some ISPs do it to be nasty. ๐Ÿ˜‰

                        Mine is virtually static.

                        I don't worry if my address becomes known. I just don't go out of my way to advertise it.

                        PfSense running on Qotom mini PC
                        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                        UniFi AC-Lite access point

                        I haven't lost my mind. It's around here...somewhere...

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

                          @jknott said in GRC closed instead of stealth ports?:

                          I don't worry if my address becomes known. I just don't go out of my way to advertise it.

                          Exactly..

                          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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