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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>So from the Internet you should block NTP packets to your CallManager or to anything that isn’t doing NTP. NTP shoud have a whitelist.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Wondering how many people have NTP from the Internet allowed to anything unless you’re a ISP.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> Read the article several times and found this;<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>http://blog.cloudflare.com/understanding-and-mitigating-ntp-based-ddos-attacks<o:p></o:p></span></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 #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> cisco-voip [mailto:cisco-voip-bounces@puck.nether.net] <b>On Behalf Of </b>Steve Rubin<br><b>Sent:</b> Monday, February 03, 2014 7:56 PM<br><b>To:</b> cisco-voip<br><b>Subject:</b> [cisco-voip] NTP DDOS Vulnerability in 8.x/9.x<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><br><br><a href="http://blogs.cisco.com/security/when-network-clocks-attack/" target="_blank">http://blogs.cisco.com/security/when-network-clocks-attack/</a><br><br>Call Manager and Unity Connection (likely other products as well) are<br>vulnerable to the very attack that Cisco blogs about.<br><br><br>Bug is CSCum76937. <br><br>-- <br>Steve Rubin <br><a href="mailto:ser@layer42.net">ser@layer42.net</a><br>Layer42 Networks <br><a href="http://www.layer42.net/" target="_blank">http://www.layer42.net/</a><br><br><br><br><br><br><br>_______________________________________________<br>cisco-voip mailing list<br><a href="mailto:cisco-voip@puck.nether.net">cisco-voip@puck.nether.net</a><br><a href="https://puck.nether.net/mailman/listinfo/cisco-voip" target="_blank">https://puck.nether.net/mailman/listinfo/cisco-voip</a><br><br><br><span style='color:white'>itevomcid</span> <o:p></o:p></p></div></body></html>