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    Unknown Android Device

    General pfSense Questions
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    • S
      slimypizza
      last edited by

      I recently noticed on my DHCP Server page, that what appears to be an Android device (identified as android-3854ef10afd0d6ff) had received a DHCP address. That was a red flag to me because I don’t have any Android devices. I assigned a static IP and made a LAN rule to block that address just to contain it which seems to be working. Per the logs, the ‘device’ tries to contact either DNS (53) or a couple of IP’s in China every few seconds (203.119.211.219, 203.119.217.116, 203.119.205.154). Any ideas what could be happening? I did reboot pFsense and the device came back. The only new devices I have at the house are Alexa dots which I have assigned static IP’s to and are accounted for. Blocking communication of the unknown device has no effect on the performance of the Alexa dots so I don’t believe they’re associated.

      NollipfSenseN 1 Reply Last reply Reply Quote 0
      • NollipfSenseN
        NollipfSense @slimypizza
        last edited by

        @slimypizza Posting situations such as this makes no sense. The device must have came from those who has access to your LAN...either household or guest. I even believe your Alexa uses Android. For sure, pfSense has NOTHING to do with this issue.

        pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
        pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

        1 Reply Last reply Reply Quote 0
        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          That's just the hostname whatever it is reports. Android does use a naming scheme like that but it could be anything with a spoofed name.

          Check the MAC address, what is the OUI? That too could be spoofed of course.

          Install the nmap package run it against that host.

          Change your wifi passphrase if you're in any doubt.

          Steve

          1 Reply Last reply Reply Quote 0
          • NollipfSenseN
            NollipfSense
            last edited by NollipfSense

            He could renew the lease to see whether the device appears and got a new IP...

            pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
            pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

            JKnottJ 1 Reply Last reply Reply Quote 0
            • JKnottJ
              JKnott @NollipfSense
              last edited by

              @NollipfSense

              It should normally get the same address.

              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...

              NollipfSenseN 1 Reply Last reply Reply Quote 0
              • NollipfSenseN
                NollipfSense @JKnott
                last edited by NollipfSense

                @JKnott I realized that...maybe I should have said the device accepts IP however at least he would be able to know whether the device is active and powered.

                pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
                pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

                1 Reply Last reply Reply Quote 0
                • S
                  slimypizza
                  last edited by

                  Thanks all. I did check the MAC, renewed the lease (before I gave it a static IP) and began taking devices offline to narrow down what this could be. Then….. I discovered a wifi picture frame my daughter had gotten and set up on the network. That was it. I’m not happy that it communicates to China with such frequency but will leave it be for now. Thanks for the feedback.

                  JKnottJ NollipfSenseN 2 Replies Last reply Reply Quote 0
                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Mmm, worrying. 😬

                    1 Reply Last reply Reply Quote 0
                    • GertjanG
                      Gertjan
                      last edited by

                      This DHCP server option :

                      ebab6b29-8c58-4e17-869e-a7aa6d61bb24-image.png

                      might help you.
                      When you give away your Wifi password, "people" can connect any device they want.

                      True, if the device permits a static IP / DNS / network / gateway setup, it could still communicate. Only firewall rules per device would really help = protect you.

                      Btw : connected devices nearly always 'call home'. Often, it's just the time and possible updates. Some times it's more. Before even buying stuff like this, you should 'Google them up' first.

                      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
                      • JKnottJ
                        JKnott @slimypizza
                        last edited by

                        @slimypizza said in Unknown Android Device:

                        I’m not happy that it communicates to China

                        Maybe it's spying on you! 😉

                        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...

                        1 Reply Last reply Reply Quote 0
                        • NollipfSenseN
                          NollipfSense @slimypizza
                          last edited by

                          @slimypizza said in Unknown Android Device:

                          I’m not happy that it communicates to China with such frequency

                          This below...almost always it just checking for firmware upgrade!

                          @Gertjan said in Unknown Android Device:

                          Btw : connected devices nearly always 'call home'. Often

                          pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
                          pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

                          1 Reply Last reply Reply Quote 0
                          • S
                            slimypizza
                            last edited by

                            Yes, probably spying on the whole family. HA! The frequency of interaction is about every 20 seconds. Seems excessive but the picture frame also allows for emailed photos and is probably checking for deliveries. Outbound communication only, it seems. No worries. Thank you all.

                            1 Reply Last reply Reply Quote 0
                            • P
                              Pandame43
                              last edited by

                              The device must have came from those who has access to your LAN...either household or guest. I even believe your Alexa uses Android. For sure, pfSense has NOTHING to do with this issue.

                              1 Reply Last reply Reply Quote 0
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