Irresponsible behavior on Amazon's part.
" Complaints of rampant SIP Brute Force Attacks coming from " servers with Amazon EC2 IP Addresses cause many admins to " simply drop all Amazon EC2 traffic. Generally, SIP brute " force attacks attempt to register various peer names to a " system and/or attempt to guess passwords of known/guesses " peers or endpoints.
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" The complaints mentioned this weekend show an excessive " amount of traffic; with some providers claiming 6GB of " traffic dedicated to such attacks. Since we ourselves " received an attack from an Amazon hosted server, we also " reported and complained to the Amazon NOC/Abuse depts. " " There are various techniques to assist with minimizing " DDoS and Brute Force attacks, such as limiting access " via the public internet, using strong passwords, not " mapping extension name to peer/endpoint name, limiting " simultaneous calls, and aggressively monitoring usage. " Automatic blocking of abusive IP's (fail2ban, blockhosts, " etc.) can also assist with minimizing damage.
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