SANS ISC: A Day In The Life Of A DShield Sensor

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SANS ISC InfoSec Forums

This weekend has been pretty smooth with respect to security incidents, so I thought I would show everybody what my DShield sensor is telling me about the unsolicited packets coming to my home network.  I've been submitting packets to DShield for nearly 10 years so I've got a lot of historical data I can look back through.  This is very helpful when trying to figure out if something is new, or if it's been here before. 

Here's what my report from yesterday (November 20, 2010) said:

   Day: 2010-11-20
Userid: xxxxxxxx

For 2010-11-20 you submitted 7763 packets from 1352 sources hitting 3 targets.

Port Summary
============

Port  |  Packets  |  Sources  |  Targets  |      Service       |  Name
------+-----------+-----------+-----------+--------------------+--------
------+-----------+-----------+-----------+--------------------+-----
 6881 |      7265 |      1240 |         1 |         bittorrent | Bit Torrent P2P
   23 |        76 |        75 |         1 |             telnet |
   22 |         6 |         5 |         1 |                ssh | SSH Remote Login Protocol
14043 |        16 |         5 |         1 |                    |
 1434 |         3 |         3 |         1 |           ms-sql-m | Microsoft-SQL-Monitor
   80 |         3 |         3 |         1 |                www | World Wide Web HTTP
  500 |        34 |         2 |         1 |             isakmp | VPN Key Exchange
 5060 |         2 |         2 |         1 |                sip | SIP
    0 |        17 |         1 |         1 |                    |
 8000 |         2 |         1 |         1 |              irdmi | iRDMI
44859 |         1 |         1 |         1 |                    |
49719 |         6 |         1 |         1 |                    |
 2304 |         1 |         1 |         1 |     attachmate-uts | Attachmate UTS
 8443 |         1 |         1 |         1 |         pcsync-ssl | PCSync SSL
45890 |         3 |         1 |         1 |                    |
50129 |         1 |         1 |         1 |                    |
 2489 |        15 |         1 |         1 |              tsilb | TSILB
 8880 |         1 |         1 |         1 |          cddbp-alt | CDDBP
47028 |         6 |         1 |         1 |                    |
50603 |       263 |         1 |         1 |                    |


Port Scanners
=============

    source     | Ports Scanned | Host Name
---------------+---------------+------------
  88.69.244.106|           8   | dslb-088-069-244-106.pools.arcor-ip.net
  221.1.220.185|           3   |
 166.68.134.172|           2   |
  85.114.130.94|           2   | o094.orange.fastwebserver.de
 85.192.147.126|           2   | 85-192-147-126.dsl.esoo.ru


Source Summary
==============

    source     | hostname  |packets|targets| all pkts | all trgs | first seen
---------------+-----------+-------+-------+----------+----------+------
---------------+-----------+-------+-------+----------+----------+-----
      1.53.88.8|           |   971 |     1 |     1132 |        1 | 11-20-2010
  113.22.207.92|           |   408 |     1 |      208 |        1 | 11-20-2010
 166.68.134.172|           |   296 |     1 |    12492 |        2 | 11-13-2010
  61.64.224.115|-net.net.tw|    80 |     1 |      142 |        1 | 11-18-2010
  99.159.78.228|cglobal.net|    58 |     1 |       56 |        1 | 11-20-2010
 118.166.218.29|c.hinet.net|    45 |     1 |       45 |        1 | 11-20-2010
    123.0.72.24|3.cc9.ne.jp|    44 |     1 |       47 |        1 | 11-20-2010
  41.133.190.65|.mweb.co.za|    42 |     1 |      103 |        1 | 11-18-2010
   84.252.32.21|           |    41 |     1 |       82 |        1 | 11-18-2010
   82.226.17.57|.proxad.net|    39 |     1 |       74 |        3 | 10-29-2010
   68.5.169.151|.oc.cox.net|    38 |     1 |       83 |        1 | 11-15-2010
  77.76.128.133|ilinkbg.com|    36 |     1 |       43 |       10 | 11-13-2010
213.109.234.208|           |    36 |     1 |       80 |        1 | 11-15-2010
114.156.127.176|a.ocn.ne.jp|    36 |     1 |      122 |        4 | 10-26-2010
  58.114.142.76|giga.net.tw|    34 |     1 |      107 |        1 | 11-15-2010
 41.236.243.205|.tedata.net|    34 |     1 |       39 |        1 | 11-20-2010
  111.185.35.37|albb.net.tw|    34 |     1 |       88 |        1 | 11-13-2010
    41.200.4.97|           |    33 |     1 |       30 |        1 | 11-20-2010
  116.49.85.149|vigator.com|    33 |     1 |       33 |        1 | 11-20-2010
    84.54.184.2|lingrad.net|    33 |     1 |       77 |        9 | 04-04-2010
 

As you can see, I've got a lot of unsolicited Bit Torrent traffic, and quite a few intruders trying to telnet into my home system.  All of these packets are dropped by my firewall, logged, then sent to DShield once an hour.  In a perfect world I would not be seeing any SYN packets coming at my house since I'm not running any servers here.  The large number of Bit Torrent is troubling, but I'm sure that it's because whoever owned the dynamic IP assigned to me was a Bit Torrent user and all of his peers are trying to reconnect.

So what does your home DShield report look like?  Getting anything you should not be seeing?  In fact, are you submitting DShield data from your home network?  If not, please do so!  We can use all of the packets we can get, and doing this at home is a snap.  The instructions are on the DShield site, and if you have any questions just let us know.  We run a discussion list on Google Groups, so be sure to sign up for that too.  Let us know how you use DShield via the comment link below.

Marcus H. Sachs
Director, SANS Internet Storm Center