Spoofed RFC1918 Network Source Addresses...

From: Security Consultant (listrecipientat_private)
Date: Fri Nov 15 2002 - 13:03:20 PST

  • Next message: Christian Schwede: "Strange Apache logs - maybe DDOS?"

    Hello All,
    
       I've been following the thread here regarding the IP Spoofs from
    0.0.0.0 with interest as I'm seeing something similar, but not the
    same in one of my client environments.  I see packets from a specific
    internet host that the client has associations with (which presumably
    means they are allowing certain specific traffic from that host to
    pass via the firewall to other certain hosts within the environment)
    that are directed to subnet addresses, such as 10.0.0.0 or 10.1.0.0 or
    10.1.2.0.  Lots of different combinations.  I also see other traffic
    that is either spoofed traffic or some sort of return traffic to these
    spoofed addresses as they are sourced with 10.0.0.0 or 10.1.0.0 or
    10.1.2.0 or something like that.  It is possible that the firewall or
    NAT device is improperly configured and is adding state for these
    spoofed addresses which might be destined for the internet and thus
    the return packets are making it back.  It just seems odd that the
    only external addresses appears to be hosts that are "trusted" by the
    organization.  Has anyone seen anything like this recently.  This has
    been happening for at least a week.  Thanks in advance for any help.
    
       --- Joel
    
    
    ----------------------------------------------------------------------------
    This list is provided by the SecurityFocus ARIS analyzer service.
    For more information on this free incident handling, management 
    and tracking system please see: http://aris.securityfocus.com
    



    This archive was generated by hypermail 2b30 : Sat Nov 16 2002 - 04:56:50 PST