Re: spambots and dictionary attacks

Hans Wolters <[email protected]> Fri, 17 Nov 2006 19:51:32 +0100
Newsgroups gmane.comp.security.linux
Message-ID <[email protected]>
On 17-nov-2006, at 17:02, rowland onobrauche wrote:

>
> I would like to hear from anyone that has successfully blocked
> spambots or dictionary attacks without the need of another server in
> between your mailserver and the senders.
> The mailserver on my end is exim and it is actually a virtual server,
> so i cannot really edit the exim.conf file, but have access to access,
> virtusertable, trustedusers and sendmail.cw.

One thing to block about 90% or more of the attempts made by botnets
is preventing they can mail you by logging wrongly used helo's on the  
mta.

I am running a script on my maillogs daily that is logging every  
attempt and
stores it, in this situation, in the spamikaze database.

http://spamikaze.is-a-geek.org/~hans/prevent.pl

If the storeip subroutine would be altered you could also log it to a  
file in a
format that exim uses to block ipnumbers. There is one in the current
spamikaze instance afaik.

http://spamikaze.org/

Best regards,

Hans