[Mimedefang] Blocking Dictionary Attacks

Paul Murphy Paul.Murphy at argentadiscovery.com
Tue Jun 9 14:08:06 EDT 2009

>>> Les Mikesell <les at futuresource.com> 09/06/2009 18:59 >>>
> Spammers are a lot smarter than that these days.  If you watch your logs 
> during a dictionary attack you are likely to see the messages come in 
> from dozens of different IP addresses that are obviously coordinating 
> the address space and timing so you don't see a big number of addresses 
> come in from any single source, or on any single message, or fast enough 
> to overwhelm a reasonable server.

Agreed, some are smarter - but there's enough of the old sort to make it worthwhile.

Recipient throttling, limits on the max number of recipients, etc are all worth doing - but for the specific case of a single server which tries a dictionary attack, MD is the place to trap for it.

Best Wishes,


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