Dear Nanog'er, We are facing a lot of port scan and brute force attack on port 22 (but not limited to) from Microsoft AS 8075 range toward our own infra, or toward our customers. We have sent email to abuse@microsoft.com, but no answer. source ip are: NetRange: 40.74.0.0 - 40.125.127.255 CIDR: 40.74.0.0/15, 40.112.0.0/13, 40.124.0.0/16, 40.76.0.0/14, 40.80.0.0/12, 40.125.0.0/17, 40.96.0.0/12, 40.120.0.0/14 NetName: MSFT We consider port scan and brute force on ssh port as an attack, and even as a pre-DDOS phase (could be use to install botnet, detect unpatched host, and so one). It's one thing to propose services and make money over an infra, it's an other thing to take care that you clients do not use this infra to make illegal stuffs. How do you deal with such massive amount of 'illegal' traffic ? Thank, Best Regards Marcel He are some examples (we have more than 3000 such packets per day just from them, probably Azure), and source ip is always differents of course: Flow Filtering Expression src AS 8075 and dst port 22 and packets=1 Limit Flows 40000 Sorting By Date Date_first_seen Duration Proto _IP_Addr:Port Dst_IP_Addr:Port Flags Packets 2016-02-29 14:55:20.108 0.000 6 104.45.210.69:1160 -> x.x.231:22 ...... 1 2016-02-29 14:55:20.611 0.000 6 104.45.210.69:1161 -> x.x.231:22 ...... 1 2016-02-29 14:56:41.004 0.000 6 40.76.55.204:1090 -> x.x..14:22 ...... 1 2016-02-29 14:56:41.324 0.000 6 40.76.55.204:1091 -> x.x..14:22 ...... 1 2016-02-29 15:00:05.670 0.000 6 40.76.55.204:1088 -> x.x.125:22 ...... 1 2016-02-29 15:00:06.003 0.000 6 40.76.55.204:1089 -> x.x.125:22 ...... 1 2016-02-29 15:01:17.358 0.000 6 40.76.70.58:1168 -> x.x..80:22 ...... 1 2016-02-29 15:01:17.676 0.000 6 40.76.70.58:1169 -> x.x..80:22 ...... 1 2016-02-29 15:02:42.637 0.000 6 40.76.55.204:1176 -> x.x.193:22 ...... 1 2016-02-29 15:02:42.878 0.000 6 40.76.55.204:1177 -> x.x.193:22 ...... 1 2016-02-29 15:02:48.067 0.000 6 104.45.210.69:1160 -> x.x.173:22 ...... 1 2016-02-29 15:02:48.394 0.000 6 104.45.210.69:1161 -> x.x.173:22 ...... 1 2016-02-29 15:03:18.854 0.000 6 40.121.53.153:1041 -> x.x..88:22 ...... 1 2016-02-29 15:03:19.172 0.000 6 40.121.53.153:1042 -> x.x..88:22 ...... 1 2016-02-29 15:06:36.248 0.000 6 40.76.55.204:1056 -> x.x..45:22 ...... 1 2016-02-29 15:07:31.882 0.000 6 40.76.80.17:44895 -> x.x..75:22 ...... 1 2016-02-29 15:07:32.245 0.000 6 40.76.80.17:44896 -> x.x..75:22 ...... 1 2016-02-29 15:09:08.433 0.000 6 40.76.70.58:1168 -> x.x..31:22 ...... 1 2016-02-29 15:09:08.744 0.000 6 40.76.70.58:1169 -> x.x..31:22 ...... 1 2016-02-29 15:11:45.668 0.000 6 40.76.80.17:47993 -> x.x.157:22 ...... 1 2016-02-29 15:11:45.987 0.000 6 40.76.80.17:47994 -> x.x.157:22 ...... 1 2016-02-29 15:12:09.543 0.000 6 40.76.70.58:1168 -> x.x..24:22 ...... 1 2016-02-29 15:12:09.925 0.000 6 40.76.70.58:1169 -> x.x..24:22 ...... 1 2016-02-29 15:17:05.920 0.000 6 40.76.70.58:1168 -> x.x.243:22 ...... 1 2016-02-29 15:17:06.241 0.000 6 40.76.70.58:1169 -> x.x.243:22 ...... 1 2016-02-29 15:19:21.364 0.000 6 40.83.121.211:62936 -> x.x..81:22 ...... 1 2016-02-29 15:19:21.704 0.000 6 40.83.121.211:62937 -> x.x..81:22 ...... 1 2016-02-29 15:19:45.891 0.000 6 40.76.70.58:1168 -> x.x..39:22 ...... 1 2016-02-29 15:19:46.273 0.000 6 40.76.70.58:1169 -> x.x..39:22 ...... 1 2016-02-29 15:21:52.030 0.000 6 40.76.70.58:1168 -> x.x.120:22 ...... 1 2016-02-29 15:21:52.349 0.000 6 40.76.70.58:1169 -> x.x.120:22 ...... 1 2016-02-29 15:24:07.614 0.000 6 40.76.55.204:1048 -> x.x.237:22 ...... 1 2016-02-29 15:24:07.933 0.000 6 40.76.55.204:1128 -> x.x.237:22 ...... 1 2016-02-29 15:27:31.289 0.000 6 40.121.53.153:1041 -> x.x.133:22 ...... 1 2016-02-29 15:27:31.544 0.000 6 40.121.53.153:1042 -> x.x.133:22 ...... 1 2016-02-29 15:27:59.120 0.000 6 40.76.70.58:1168 -> x.x.9.3:22 ...... 1 2016-02-29 15:27:59.440 0.000 6 40.76.70.58:1169 -> x.x.9.3:22 ...... 1 2016-02-29 15:29:30.933 0.000 6 40.76.70.58:1168 -> x.x.211:22 ...... 1 2016-02-29 15:29:31.031 0.000 6 40.76.70.58:1169 -> x.x.211:22 ...... 1 2016-02-29 15:29:33.729 0.000 6 40.76.55.204:1142 -> x.x.166:22 ...... 1 2016-02-29 15:29:34.032 0.000 6 40.76.55.204:1143 -> x.x.166:22 ...... 1 2016-02-29 15:31:41.947 0.000 6 40.76.70.58:1168 -> x.x.137:22 ...... 1 2016-02-29 15:31:42.266 0.000 6 40.76.70.58:1169 -> x.x.137:22 ...... 1 2016-02-29 15:32:10.044 0.000 6 40.121.53.153:1041 -> x.x..71:22 ...... 1 2016-02-29 15:32:10.348 0.000 6 40.121.53.153:1042 -> x.x..71:22 ...... 1 2016-02-29 15:32:10.442 0.000 6 104.45.210.69:1161 -> x.x.246:22 ...... 1 2016-02-29 15:32:10.475 0.000 6 104.45.210.69:1160 -> x.x.246:22 ...... 1 2016-02-29 15:32:29.165 0.000 6 40.121.143.132:1040 -> x.x..62:22 ...... 1 2016-02-29 15:32:29.466 0.000 6 40.121.143.132:1041 -> x.x..62:22 ...... 1 2016-02-29 15:37:07.616 0.000 6 40.76.80.17:56902 -> x.x..51:22 ...... 1 2016-02-29 15:37:07.925 0.000 6 40.76.80.17:56903 -> x.x..51:22 ...... 1 2016-02-29 15:40:04.546 0.000 6 40.121.53.153:1041 -> x.x.186:22 ...... 1 2016-02-29 15:40:04.866 0.000 6 40.121.53.153:1042 -> x.x.186:22 ...... 1 2016-02-29 15:40:28.870 0.000 6 40.76.70.58:1168 -> x.x.171:22 ...... 1 2016-02-29 15:40:29.125 0.000 6 40.76.70.58:1169 -> x.x.171:22 ...... 1 2016-02-29 15:41:57.034 0.000 6 40.76.55.204:1128 -> x.x.181:22 ...... 1 2016-02-29 15:41:57.354 0.000 6 40.76.55.204:1176 -> x.x.181:22 ...... 1 2016-02-29 16:55:49.183 0.000 6 40.117.96.192:1120 -> x.x.163:22 ...... 1 2016-02-29 16:55:49.183 0.000 6 40.117.96.192:1120 -> x.x.176:22 ...... 1 2016-02-29 16:55:49.183 0.000 6 40.117.96.192:1120 -> x.x.206:22 ...... 1 2016-02-29 16:55:49.183 0.000 6 40.117.96.192:1120 -> x.x.158:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.185:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.251:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.255:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.141:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.136:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.235:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.242:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.240:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.100:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.244:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x.217:22 ...... 1 2016-02-29 16:55:49.186 0.000 6 40.117.96.192:1120 -> x.x..72:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.221:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.5.4:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.150:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.145:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.119:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x..52:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x..75:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.127:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x..22:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x..77:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.246:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x.137:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x..85:22 ...... 1 2016-02-29 16:55:49.187 0.000 6 40.117.96.192:1120 -> x.x..35:22 ...... 1