RE: Strange Port 0 Traffic

From: Andre Ludwig (
Date: 11/14/03

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    Date: Fri, 14 Nov 2003 12:58:36 -0800

    Port 0 has been used to fingerprint OS's remotely in a few tools.

    Andre Ludwig, CISSP

    -----Original Message-----
    From: []
    Sent: Thursday, November 13, 2003 2:41 PM
    Subject: Strange Port 0 Traffic

    I am seeing a lot of traffic lately coming from different external
    sources using UDP originating from a source port of 10000 and coming to
    my various firewall addresses with a destination port of 0.

    I ran tcpdump traces for this traffic both internally and externally for
    about 2 weeks. The traces showed no internal servers/desktops/devices
    making these connections, only external machines sending these packets
    to the firewalls.

    The data in the packet is gibberish; looks like it might be encrypted.
    Is anyone else seeing this kind of traffic?

    Attached is a sanitized trace of some of these packets.

    Josh Berry
    Information Security Group

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