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<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>I am setting
filters, etc. on variables that attackers can send asterisk when they call (for
example when they initially call into asterisk).<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>So far, I am
filtering:<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>exten<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>CALLERID(name)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>CALLERID(num)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>What other fields
or variables would an attacker be able to use in the packets that they send when
placing the call to asterisk?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>Further, I am
assuming that in the case that an attacker, first, simply dials in normally and
then after reaching voice prompts or other, starts his/her attack, then all I
need to filter in that case is exten. Anything else here as well?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'>Thanks!!<o:p></o:p></span></p>
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