SMURF amplifier block list

Jeremy Porter jerry at
Tue Apr 21 01:34:04 UTC 1998

In message <199804210004.SAA02213 at>, Dave Andersen writes:
>   Not really.  The lists of smurfable addresses on the net have contained
>network numbers for a while now, or so goes the rumor on other lists.  It
>could have come through someone scanning addresses sequentially to find a
>broadcast address (mm, exciting job), or it could have come from a clueful
>cracker somewhere else.  It doesn't take too many brains to use the
>prepackaged hacking/crashing programs people can download off Bugtraq.
>(OTOH, there are quite a few clueful crackers out there, who've found that
>reading the RFCs is a good thing.  Crackers reading RFCs may not be a good
>thing. :-)

If these attackers had been reading the RFCs years ago, these problems
would have been fixed on a much smaller network, causing less total
disruption.  But of course they were exploiting other security holes at
the time.  Security holes DON'T get fixed until they are exploited
on a large scale, this applies to gaping lapses in Internet design, due
to its origin of "cooperative" networks, things like sendmail and bind
defaulting to "trust everyone", i.e. sendmail relaying, and bind
additional RR poisoning.

There simply are too many things broken for someone to considering
fixing all the known issues before they are abused.  But
eventually we will see source filtering and "no ip directed broadcast",
but if sendmail relaying is any indication, it will be another year
and 1/2 before the first 90% of the problem is fixed.

Jeremy Porter, Freeside Communications, Inc.      jerry at
PO BOX 80315 Austin, Tx 78708  | 512-458-9810

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