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</o:shapelayout></xml><![endif]--></head><body lang=ES-MX link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'>I saw this kind of fraud last year, we are a small carrier in Mexico city, the attackers send a burst of calls to one of our customer’s 1-800 number, we realized by the huge amount of calls with really short duration –10 seconds at most- and it caused our customer was out of service temporarily as the PBX was exhausted. The attack came from an specific number from another local carrier, although it was identified the user was a PBX extension and allegedly abused by hackers hence no direct responsible identified. We block the originating number to prevent much more calls were completed.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> VoiceOps [mailto:voiceops-bounces@voiceops.org] <b>On Behalf Of </b>Geoffrey Mina<br><b>Sent:</b> jueves, 03 de abril de 2014 10:01 a.m.<br><b>To:</b> VoiceOps<br><b>Subject:</b> [VoiceOps] Toll-Free Fraud/Spam<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We are seeing a relatively high number of strange calls hitting a portion of our Toll-Free numbers. The ANIs are mostly disconnected/invalid. When our system answers, we hear silence, a DTMF tone, and then a fast busy on the inbound RTP stream.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We are seeing this over multiple TF vendors. Is anyone else seeing anything like this out in the wild?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Geoff<o:p></o:p></span></p></div></div></div><HR>
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