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<p class=MsoNormal><span lang=EN-US>&gt; Use fail2ban.&nbsp; Also, read some of
the security advisories from earlier this year about being sure to always use a
FILTER statement whenever you're dialing using &gt; a variable (most notably
${EXTEN}).&nbsp; <a
href="http://downloads.asterisk.org/pub/security/AST-2010-002.html">http://downloads.asterisk.org/pub/security/AST-2010-002.html</a><br>
<br>
</span><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p></o:p></span></p>

<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'>Thanks Warren!!<o:p></o:p></span></p>

<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p>&nbsp;</o:p></span></p>

<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><o:p>&nbsp;</o:p></span></p>

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<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> asterisk-users-bounces@lists.digium.com
[mailto:asterisk-users-bounces@lists.digium.com] <b>On Behalf Of </b>Warren
Selby<br>
<b>Sent:</b> Saturday, August 07, 2010 1:35 PM<br>
<b>To:</b> Asterisk Users Mailing List - Non-Commercial Discussion<br>
<b>Subject:</b> Re: [asterisk-users] Security - What inbound variables can
attackers populate or use when calling?<o:p></o:p></span></p>

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<p class=MsoNormal><span lang=EN-US><o:p>&nbsp;</o:p></span></p>

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<p class=MsoNormal><span lang=EN-US>On Fri, Aug 6, 2010 at 10:53 PM, &lt;<a
href="mailto:jwexler@mail.usa.com">jwexler@mail.usa.com</a>&gt; wrote:<o:p></o:p></span></p>

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<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
lang=EN-US style='font-size:10.0pt;color:#1F497D'>Someone from Amsterdam was
trying to register yesterday using an automated program which tried roughly
1,000 or so username password combinations before I shut asterisk down and
added his/her ip to iptables to drop it. I wonder if I can configure the system
to automatically detect such an attack in progress (e.g., a 1,000+ registration
failures from the same ip is an &#8216;attack&#8217;) and the ip&#8217;s to
iptables, hosts.deny, etc. on the fly. That might be another topic I guess?</span><span
lang=EN-US><o:p></o:p></span></p>

<p class=MsoNormal><span lang=EN-US><br clear=all>
<o:p></o:p></span></p>

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<p class=MsoNormal><span lang=EN-US><br>
Use fail2ban.&nbsp; Also, read some of the security advisories from earlier
this year about being sure to always use a FILTER statement whenever you're
dialing using a variable (most notably ${EXTEN}).&nbsp; <a
href="http://downloads.asterisk.org/pub/security/AST-2010-002.html">http://downloads.asterisk.org/pub/security/AST-2010-002.html</a><br>
<br>
-- <br>
Thanks,<br>
--Warren Selby<br>
<a href="http://www.selbytech.com">http://www.selbytech.com</a><o:p></o:p></span></p>

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