[CentOS] Sendmail SMTP Brute-Force Attack

Fri Jun 15 00:58:16 UTC 2012
Gustavo Lacoste <gustavo at lacosox.org>

The problem with my server is: I use it to offer webhosting services. Some
customers using Outlook are blocked because they use black listed ips (ips
simply are dynamic).



With Kind Regards,

     Gustavo A. Lacoste Z.
     Curacautín - Chile
     Skype: knxroot
     Msn & Gtalk: knx.root [at] gmail.com
     Home page: http://www.lacosox.org
- -
*Por favor, evite enviarme documentos adjuntos en formato Word o PowerPoint.
Lea http://www.gnu.org/philosophy/no-word-attachments.es.html*


2012/6/14 John R Pierce <pierce at hogranch.com>

> On 06/14/12 4:33 PM, Gustavo Lacoste wrote:
> > I need help for STOP this spamers right now.
> >
> > Thanks in advance to anyone who can guide me
>
> 2 of the three relay IPs listed in your log fragment are listed on
> spamhaus' Zen combined list, http://www.spamhaus.org/zen/
>
> this is free for use by low volume non-commercial email servers. see the
> terms linked on the above URL.
> adding the following line to your sendmail.mc file, then rebuilding the
> .cf and restarting sendmail would reject all mail connections from
> servers listed via Spamhaus.
>
> FEATURE(dnsbl,`zen.spamhaus.org',`Message from $&{client_addr} rejected
> - see http://www.spamhaus.org/SBL/sbl-rationale.html') dnl
>
>
> (note this file is in M4 syntax, and has to use 'funny' quoting, with a
> ` as the opening quote).
>
>
>
>
>
> --
> john r pierce                            N 37, W 122
> santa cruz ca                         mid-left coast
>
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