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    Port 6667 - kids brought something home from school

    Scheduled Pinned Locked Moved IDS/IPS
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    • 2
      2chemlud Banned
      last edited by

      Hi!

      Apparently one of the kids brought home some linux trojan on his school notebook, I found info on

      yoyo

      Trinity

      in this database

      http://www.simovits.com/trojans/trojans.html

      Any advice what to do besides reinstalling the OS completely (to be done over weekend…)?

      Kind regards

      chemlud
      [ma port 6667.jpg](/public/imported_attachments/1/ma port 6667.jpg)

      1 Reply Last reply Reply Quote 0
      • bmeeksB
        bmeeks
        last edited by

        I have no suggestions for how to clean it, but I am curious what detected it.  Did Snort or Suricata fire an alert, or did you see unusual activity in the firewall log (or maybe both)?

        Bill

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        • N
          Nullity
          last edited by

          @2chemlud:

          Hi!

          Apparently one of the kids brought home some linux trojan on his school notebook, I found info on

          yoyo

          Trinity

          in this database

          http://www.simovits.com/trojans/trojans.html

          Any advice what to do besides reinstalling the OS completely (to be done over weekend…)?

          Kind regards

          chemlud

          Are you sure they have a virus?

          They could just be chatting on IRC. IRC commonly connects on TCP ports 6660-6669, with 6667 being the most common.

          Please correct any obvious misinformation in my posts.
          -Not a professional; an arrogant ignoramous.

          1 Reply Last reply Reply Quote 0
          • K
            kejianshi
            last edited by

            When I see the words linux and virus or linux and trojan in the same sentence, my first thought is "false positive"…

            Of course, it can be done...  It just takes work on the part of the linux user to install the bug.

            Is it a WINE compatible windows thing maybe?  Or just nothing?

            1 Reply Last reply Reply Quote 0
            • DerelictD
              Derelict LAYER 8 Netgate
              last edited by

              IRC is also commonly used by bad things for command and control.

              Chattanooga, Tennessee, USA
              A comprehensive network diagram is worth 10,000 words and 15 conference calls.
              DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
              Do Not Chat For Help! NO_WAN_EGRESS(TM)

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              • 2
                2chemlud Banned
                last edited by

                Dear all!

                Many thanks for replies! Snort detected it. Nothing in the firewall logs. Today, the same thing, but only one IP blocked by Snort, but three others (TCP-s) blocked by standard block rule in firewall…

                I learned that there are some programmers and game IRC channels booked on this notebook... :-)

                Kids are always a surprise, every day again...

                Kind regards for your input!

                chemlud

                PS: No wine on this device... :-)

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                • 2
                  2chemlud Banned
                  last edited by

                  PPS:

                  Wanted to have a look at the firewall logs, but apparently size is fixed to 500 kB, and the log was filled with nonsense "allow multicast" messages (IGMP 224.0.0.22 and stuff like that, no rule indicated why this nonsense is logged…), so that all relevant info from yesterday is gone.

                  I tried to find the place where I can increase the log-size, but without success... Any suggestion where to increase the size of the log files?

                  Many thanx in advance!

                  chemlud...

                  Found it! Increased log size, but it still logs this 224.0.0.22 IGMP although I have for more than a year now an "allow" rule for that without (!) logging (to stop flooding the logs), but pfSense simply doesn't care and logs this traffic anyway. Don't know what to do with that....

                  PPPS: Erased the allow rule for IGMP from LAN to 224.0.0.22 and set it up newly, but again this traffic was in the log file. Switched to "block" and now it subsided... Strange....

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