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    Identifying Rogue Traffic

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • J Offline
      james_h
      last edited by

      I killed the state and the traffic ceased but I have no idea where it was coming from.

      05a2abc8-98b8-47ee-9001-78e5e0c7823b-image.png

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      • N Offline
        Normandy214
        last edited by

        Don't know if this will help you figure this out: but something to consider:
        Port 57621 using UDP is most commonly associated with Spotify, particularly with Spotify Connect and Spotify's peer-to-peer (P2P) local file synchronization features. This port is used for broadcast and discovery purposes on local networks, where Spotify clients use UDP 57621 to detect other Spotify devices and share playlist and local file information. Several security and networking communities, along with Spotify documentation and user reports, confirm this usage as the main known application for UDP port 57621.

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        • J Offline
          james_h @Normandy214
          last edited by james_h

          @Normandy214 said in Identifying Rogue Traffic:

          Don't know if this will help you figure this out: but something to consider:
          Port 57621 using UDP is most commonly associated with Spotify, particularly with Spotify Connect and Spotify's peer-to-peer (P2P) local file synchronization features. This port is used for broadcast and discovery purposes on local networks, where Spotify clients use UDP 57621 to detect other Spotify devices and share playlist and local file information. Several security and networking communities, along with Spotify documentation and user reports, confirm this usage as the main known application for UDP port 57621.

          Thanks thats good info, will keep an eye on it. My real confusion is how can an IP with no MAC Address create a state and be sending all that traffic. Really strange.

          Been nominal so far since I killed it manually.

          2d048372-3637-488c-b76c-44be925ca358-image.png

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          • S Offline
            SteveITS Rebel Alliance @james_h
            last edited by

            @james_h just to ask do you have anything in 172.16.0.0/12 that has a mask wider than /24?

            Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
            When upgrading, allow 10-15 minutes to reboot, or more depending on packages, and device or disk speed.
            Upvote ๐Ÿ‘ helpful posts!

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            • M Offline
              marvosa @SteveITS
              last edited by

              In the future, to assess traffic in real-time, consider installing ntopng. You can also use softflowd to export netflow data to a netflow collector to analyze traffic patterns and bandwidth usage.

              Without tools like these, tracking specific bandwidth usage can be a challenging task.

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              • J Offline
                james_h @SteveITS
                last edited by

                @SteveITS said in Identifying Rogue Traffic:

                @james_h just to ask do you have anything in 172.16.0.0/12 that has a mask wider than /24?

                No which is the strange thing to me, no idea where this traffic originated from.

                8743f137-b13d-494f-b769-73aa844445c6-image.png

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                • J Offline
                  james_h @marvosa
                  last edited by

                  @marvosa said in Identifying Rogue Traffic:

                  In the future, to assess traffic in real-time, consider installing ntopng. You can also use softflowd to export netflow data to a netflow collector to analyze traffic patterns and bandwidth usage.

                  Without tools like these, tracking specific bandwidth usage can be a challenging task.

                  Thanks for the advice, will take a look at that for future.

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                  • patient0P Offline
                    patient0 @james_h
                    last edited by

                    @james_h what is odd is that it originates from PRIVATE and goes out on FIREWAN and is not NAT-ed.

                    What traffic are you allowing on PRIVATE? Source 'PRIVATE net'|10.10.110.0/24 only or any?

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                    • J Offline
                      james_h @patient0
                      last edited by

                      @patient0 said in Identifying Rogue Traffic:

                      @james_h what is odd is that it originates from PRIVATE and goes out on FIREWAN and is not NAT-ed.

                      What traffic are you allowing on PRIVATE? Source 'PRIVATE net'|10.10.110.0/24 only or any?

                      These are the rules for PRIVATE, I guess I could change source to "PRIVATE SUBNET" ?

                      2c3a3a51-e8f5-4660-988a-a20cde122017-image.png

                      I wander if this is the problem, I cant remember what this was here for, maybe to unclutter the block log below.

                      faf3f228-d67b-46b1-9acd-09891cc39a32-image.png

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                      • S Offline
                        SteveITS Rebel Alliance @james_h
                        last edited by

                        @james_h PRIVATE is the interface? Normally traffic from an interface to other devices doesn't go through the firewall. That would imply the 2 open states are traffic from devices on that interface to pfSense. The block rules above block to certain ports. Left click the states column and it should show you the open states. But it's passed only 154 MB so seems a rather small amount of traffic.

                        Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                        When upgrading, allow 10-15 minutes to reboot, or more depending on packages, and device or disk speed.
                        Upvote ๐Ÿ‘ helpful posts!

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                        • patient0P Offline
                          patient0 @james_h
                          last edited by

                          @james_h it's more the last rule with 'PreferFIBRE'. The default allow-all rule after installation is source 'LAN subnets' and the rest any.

                          You rule allow anything as source on the PRIVATE interface. If you do expect traffic with source IPs of PRIVATE subnet then changing it from * to 'PRIVATE subnet' would have blocked the 172.20.* traffic.

                          Are the 'admin_devices' all in the PRIVATE subnet?

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                          • J Offline
                            james_h @patient0
                            last edited by

                            @patient0 said in Identifying Rogue Traffic:

                            @james_h it's more the last rule with 'PreferFIBRE'. The default allow-all rule after installation is source 'LAN subnets' and the rest any.

                            You rule allow anything as source on the PRIVATE interface. If you do expect traffic with source IPs of PRIVATE subnet then changing it from * to 'PRIVATE subnet' would have blocked the 172.20.* traffic.

                            Are the 'admin_devices' all in the PRIVATE subnet?

                            Yes I think thats what I should do. The admin devices are indeed in the PRIVATE subnet.

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