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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>The details of the source IP are available in the asterisk security log (if you have that enabled) – but that particular attack hides its address from the messages file.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It’s essential that you secure your PBX; there are options ranging from free to commercial. Have a look at:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><a href="http://www.voip-info.org/wiki/view/Asterisk+security">http://www.voip-info.org/wiki/view/Asterisk+security</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It’s easy to get a $20,000 phone bill, so take securing your PBX seriously.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>-M-<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> asterisk-users-bounces@lists.digium.com [mailto:asterisk-users-bounces@lists.digium.com] <b>On Behalf Of </b>Motty<br><b>Sent:</b> Wednesday, December 02, 2015 1:12 PM<br><b>To:</b> Asterisk Users Mailing List - Non-Commercial Discussion; motty.cruz@gmail.com<br><b>Subject:</b> [asterisk-users] Failed to authenticate device 100<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hello, I continued to see this errors in the logs: <br><br><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>[2015-12-02 10:05:57] NOTICE[19949]: chan_sip.c:23277 <span class=spelle>handle_request_invite</span>: Failed to authenticate device 100<a href="mailto:sip:100@xx.xx.xx.xx"><sip:100@xx.xx.xx.xx></a>;tag=10cdeaf7<br><br>how do I guard against this kinds of attacks? Also, to get the IP address from where this attack come from I use the following command "tcpdump -lni eth0 -f "udp port 5060" is there an easy way to get the attacker's IP? <br><br>Thanks, <br>Motty</span><o:p></o:p></p></div></body></html>