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    Snort Issue false PSNG_UDP_FILTERED_PORTSCAN

    Scheduled Pinned Locked Moved pfSense Packages
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    • M Offline
      Macom2007
      last edited by

      Can someone explain the reason for this snort entry :

      PROTO:255 PSNG_UDP_FILTERED_PORTSCAN Attempted Information Leak 178.xxx.x.xxx empty -> 188.xx.xxx.xx empty 122:21:1 01/05-11:24:04

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      • marcellocM Offline
        marcelloc
        last edited by

        If traffic port is 53 then probably it's a false positive from dns traffic.

        Treinamentos de Elite: http://sys-squad.com

        Help a community developer! ;D

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        • M Offline
          Macom2007
          last edited by

          Thanks. Prot is marked with 255, DPORT and SPORT are empty. Can be DNS, or ?

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          • H Offline
            HOD
            last edited by

            Hi

            is it secure to ignore this 122:21 alerts? I got arround 20 alerts every hour.
            1 of 10 IPs that snort blocks are recommend for my network.
            I'am a litte bit confused about this alert, maybe an attack or not…

            greetz HOD

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            • M Offline
              Metu69salemi
              last edited by

              @Macom2007:

              Thanks. Prot is marked with 255, DPORT and SPORT are empty. Can be DNS, or ?

              Certainly not dns, because destination port should be tcp/udp 53
              That protocol 255 is showing to be reserved. Don't know what it is

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              • C Offline
                CS
                last edited by

                I get this alert because of Skype software. When one of my LAN hosts has a voice/video conversation with specific people (it means specific Skype versions) I get this alert periodically during the call.  ;)

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                • I Offline
                  iFloris
                  last edited by

                  FaceTime also generates this alert.

                  one layer of information
                  removed

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