User unknown attack?

[Scott Silva]

Timothy Barhorst spake the following on 11/30/2006 12:39 PM:
> Over the last three days, our Mailscanner e-mail server has received >
> 100K attempts to a single BOGUS username  ( threateningmessage at vwg.com )
> 
> Sendmail always responds with a User unknown message … but what is the
> logic of sending this many messages?
> 
> All of them come from different source addresses so I’m pretty sure it’s
> some kind of spamming technique.. but not the usual dictionary attack I see.
> 
>  
> 
> Should I be concerned??
> 
>  
> 
> Tim Barhorst
> 
>  
> 
It could be someones attempt at a denial of service attack using servers that
bounce instead of reject. It would be directed at the vwg.com domain which is
a wholesale grocery company.

-- 

MailScanner is like deodorant...
You hope everybody uses it, and
you notice quickly if they don't!!!!