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    Firewall UDP ? Attack !! Or Normal ?

    Scheduled Pinned Locked Moved Firewalling
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    • JeGrJ
      JeGr LAYER 8 Moderator @A Former User
      last edited by

      @silence said in Firewall UDP ? Attack !! Or Normal ?:

      Today I go back to the office, and when I check my wan (it doesn't work) for some reason it's as if my isp has disconnected me completely. (I already sent the report to my isp and they are evaluating the situation)
      but this confirms once again that something is not right in that wan.

      Huh? Causality vs. correlation. Because you seem to have strange traffic and now your ISP supposedly has cut you off that confirms anything? That's no troubleshooting or debugging, that is pure guessing and crystal ball reading ๐Ÿ˜‰

      I'd check my ISP first to confirm that sth. was amiss on my line and that's why they disconnected me. Could also be just a faulty uplink, problem with the ISP itself etc. etc. All other things are just guesses and no evidence there's something not right on your WAN.

      Cheers

      Don't forget to upvote ๐Ÿ‘ those who kindly offered their time and brainpower to help you!

      If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

      ? 1 Reply Last reply Reply Quote 0
      • ?
        A Former User @JeGr
        last edited by

        @bingo600 @bmeeks @Gertjan @JeGr @johnpoz @SteveITS Updates:

        Another ip range and another port equal to udp directed to my wan.

        I don't want to hear the obvious, I ignore this kind of traffic alright, but what I'm looking for is to come to a conclusion, what are they trying to do?

        52984426-9e53-44e7-ab8f-da1abbae98ef-image.png

        81988920-8d79-4bff-b162-db424565425c-image.png

        If anyone has anything, I'm open to hearing.

        johnpozJ noplanN 3 Replies Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @A Former User
          last edited by

          @silence well 2096 is NBX-DIR, what that is used for - not sure.. cpanel something most likely from the info given here

          https://www.speedguide.net/port.php?port=2096

          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 1
          • noplanN
            noplan @A Former User
            last edited by

            @silence

            Haha u r being hacked cuz of a misconfiguration of your firewall

            Ok fair...
            So now where are is the rulset and what services r u providing behind your firewall

            BR
            NoPlan

            D 1 Reply Last reply Reply Quote 0
            • D
              deanfourie @noplan
              last edited by

              @noplan but........

              The traffic's being..............blocked?

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

                @silence what is the dest port? That is source port 2096? For all we know your generating the traffic and not allowing the answer?

                I first read it as that was your IP and port.. But your hiding what port they are going to?

                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

                noplanN 1 Reply Last reply Reply Quote 0
                • noplanN
                  noplan @A Former User
                  last edited by

                  This post is deleted!
                  1 Reply Last reply Reply Quote 0
                  • noplanN
                    noplan @johnpoz
                    last edited by

                    @johnpoz

                    without knowning what services he is providing behind his firewall to his clients I think we are not able to help him out, especially minding the early posts and informations (VPN inherit IP and traffic and on and on )

                    the next step for him will be to set up surricata and monitor this inbound WAN traffic on UDP against every avail list for the IDS/IPS system
                    ๐Ÿ‘ผ ๐Ÿ‘ผ ๐Ÿ‘ผ ๐Ÿ‘ผ

                    @deanfourie yes I know that he blocked that UDP Traffic,
                    but he @Silence never told us what services he is providing behind his firewall so maybe this is traffic is what his clients are requesting but he is blocking (think about 200 clients as he told, so a lot of nasty stuff can happen)

                    until there he provides us with more info lets sing all together ...
                    ๐ŸŽ™
                    I don't practice Santeria, I ain't got no crystal ball ....

                    ? 2 Replies Last reply Reply Quote 0
                    • ?
                      A Former User @noplan
                      last edited by

                      @noplan @bingo600 @bmeeks @deanfourie @Gertjan @JeGr @johnpoz @noplan @SteveITS

                      Hey guys I'm back today again (tried to use this service and I keep getting weird traffic this time the port is 1987/UDP

                      and the range of ips are different from the view above...

                      As I see this port could be a Trojan.

                      3802ba4b-c447-4d48-a184-916ba868bdb5-image.png

                      70505e73-334f-4e3b-8aea-fc1704e9858c-image.png

                      noplanN 1 Reply Last reply Reply Quote 0
                      • ?
                        A Former User @noplan
                        last edited by

                        @noplan said in Firewall UDP ? Attack !! Or Normal ?:

                        never told us what services he is providing behind his firewall

                        It's just my router (I don't have any services behind it)

                        @johnpoz said in Firewall UDP ? Attack !! Or Normal ?:

                        I first read it as that was your IP and port.. But your hiding what port they are going to?

                        destination port were random at that time.

                        1 Reply Last reply Reply Quote 0
                        • noplanN
                          noplan @A Former User
                          last edited by noplan

                          @silence

                          have you checked you LAN ?

                          found this after 2 sec of looking ...

                          2c2e4bf7-7712-4ad9-9973-3cf1bbceec29-image.png

                          i checked some of your source IPs ...
                          for me with lack of coffee at the moment those sources looking like random chatter on the wire
                          the wired thing is they are trying to get to dest port 1987 ...
                          so you have to look into it

                          everything else is guessing
                          brNP

                          ? 1 Reply Last reply Reply Quote 0
                          • ?
                            A Former User @noplan
                            last edited by

                            @noplan said in Firewall UDP ? Attack !! Or Normal ?:

                            have you checked you LAN ?

                            yes, all sure.

                            noplanN 1 Reply Last reply Reply Quote 0
                            • noplanN
                              noplan @A Former User
                              last edited by

                              @silence

                              So let's wrap it up

                              There is no attack
                              Get rid of that stupid rule
                              Mark the topic as solved
                              And be aware that none of your clients is going to sue you for faulty security consulting

                              BR NP without coffee

                              ? 1 Reply Last reply Reply Quote 0
                              • D
                                deanfourie
                                last edited by

                                bill-hader-watching.gif

                                1 Reply Last reply Reply Quote 1
                                • ?
                                  A Former User @noplan
                                  last edited by

                                  @noplan said in Firewall UDP ? Attack !! Or Normal ?:

                                  There is no attack

                                  Excellent, I'll mark the issue as resolved, at the end I was informed the office is offline due to ransomware.

                                  In short, if I had something pointing to my wan trying to achieve this, and in the end I achieved it in one way or another. But hey, none of this doesn't matter.

                                  NOTE: Never see massive noise as normal noise

                                  noplanN 1 Reply Last reply Reply Quote 0
                                  • noplanN
                                    noplan @A Former User
                                    last edited by

                                    @silence

                                    So there was something fishy (ransomware as you mentioned) on your LAN behind your pfS

                                    BR np

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