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    Firewall UDP ? Attack !! Or Normal ?

    Scheduled Pinned Locked Moved Firewalling
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    • ?
      A Former User @bingo600
      last edited by

      @bingo600 said in Firewall UDP ? Attack !! Or Normal ?:

      Why would someone "waste" 33Mbit/s bw on attacking you ?

      I don't know, I'm just trying to understand what's going on...and why I can't use my IP xD

      bmeeksB 1 Reply Last reply Reply Quote 0
      • bmeeksB
        bmeeks @A Former User
        last edited by bmeeks

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

        @bingo600 said in Firewall UDP ? Attack !! Or Normal ?:

        Why would someone "waste" 33Mbit/s bw on attacking you ?

        I don't know, I'm just trying to understand what's going on...and why I can't use my IP xD

        Don't focus too much on it being an attack. It really does appear more likely to be a misconfigured box somewhere else pointing to what is now the "wrong IP" for some data path. And because the traffic is UDP, the sender will have no idea the data is not getting where he wants it. He will just keep sending what he was set up to send. And with UDP that is by design -- the sender just "assumes" the data got there. And by "he", I don't mean a human. I'm thinking a dumb device like maybe a dedicated point-to-point hardware device.

        So assuming somebody once had a device configured to send a set of data via UDP to the IP you now have, if that device was not reconfigured to the new IP, it would still be streaming the same stuff to the old IP. Now, like @johnpoz said earlier, you would think someone at the other end of the session would notice things were not right and look into it. But who knows ???

        GertjanG ? 2 Replies Last reply Reply Quote 2
        • GertjanG
          Gertjan @bmeeks
          last edited by

          @bmeeks
          Yes, very that ๐Ÿ‘

          The issue will be over if this 'some one' will finally check the logs of his / this device, understand that some cron (?) task somewhere is using hard coded IP or domain name, and it fails now, or at least doesn't do what it should be doing.
          He will update his stuff, and the issue will be gone.

          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
          • ?
            A Former User @bmeeks
            last edited by

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

            I don't mean a human.

            Totally agree with you, the only problem is because from so many different IPs?

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

              @bingo600 @bmeeks @Gertjan @johnpoz @SteveITS

              Guys, I bring you a new update, about the case...

              During the weekend I am not in the office and I usually have some alerts that help me monitor the service remotely.

              Well, this alert appears during Saturday morning.

              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.

              JeGrJ 1 Reply Last reply Reply Quote 0
              • 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
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