Hi, I'm a researcher of DNS vulnerabilities. It loos like random subdomain attacks (water tourtue attack). This is the data of my rate-limitted openresolver as a honeypot. http://www.e-ontap.com/dns/todaydowngov.txt http://www.e-ontap.com/dns/todaydown.txt (You can not view these page if you are using 8.8.8.8, sorry.) Raw logs of my Unbound (Time is JST) local/etc/unbound% grep "\.faa\.gov" unbound.log | grep "SERVFAIL" | head -5 Mar 26 12:00:35 unbound[48103:0] error: SERVFAIL <unnamed568.orphaned.faa.gov. A IN>: exceeded ratelimit for zone faa.gov. Mar 26 12:00:35 unbound[48103:0] reply: 24.199.82.210 unnamed568.orphaned.faa.gov. A IN SERVFAIL 9.226781 0 45 Mar 26 12:04:31 unbound[48103:0] error: SERVFAIL <amax.faa.gov. A IN>: exceeded ratelimit for zone faa.gov. Mar 26 12:04:31 unbound[48103:0] reply: 24.199.82.210 amax.faa.gov. A IN SERVFAIL 15.112813 0 30 Mar 26 12:04:37 unbound[48103:0] error: SERVFAIL <dallatx.faa.gov. A IN>: exceeded ratelimit for zone faa.gov. local/etc/unbound% local/etc/unbound% grep "\.faa\.gov" unbound.log | grep "all servers" | head -5 Mar 26 12:05:26 unbound[48103:0] error: SERVFAIL <epoxy.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. from 2620:74:27::2:30 no server to query nameserver addresses not usable Mar 26 12:05:27 unbound[48103:0] error: SERVFAIL <lyndas365project.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 12:05:28 unbound[48103:0] error: SERVFAIL <lmn.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 12:05:30 unbound[48103:0] error: SERVFAIL <host244.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. upstream server timeout Mar 26 12:05:33 unbound[48103:0] error: SERVFAIL <leased-line188.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. upstream server timeout local/etc/unbound% local/etc/unbound% grep "\.faa\.gov" unbound.log | grep "all servers" | tail -5 Mar 26 13:41:08 unbound[48103:0] error: SERVFAIL <asm.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 13:41:15 unbound[48103:0] error: SERVFAIL <sas-uss.edc.nas.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 13:41:22 unbound[48103:0] error: SERVFAIL <eforms-stagedev.hq.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 13:41:23 unbound[48103:0] error: SERVFAIL <faardm-mceast2.idrac.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 13:41:28 unbound[48103:0] error: SERVFAIL <chronos3.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable local/etc/unbound% local/etc/unbound% grep "\.faa\.gov" unbound.log | grep "SERVFAIL" | tail -5 Mar 26 13:41:22 unbound[48103:0] reply: 24.199.82.210 eforms-stagedev.hq.faa.gov. A IN SERVFAIL 0.000000 0 44 Mar 26 13:41:23 unbound[48103:0] error: SERVFAIL <faardm-mceast2.idrac.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 13:41:23 unbound[48103:0] reply: 24.199.82.210 faardm-mceast2.idrac.faa.gov. A IN SERVFAIL 0.000000 0 46 Mar 26 13:41:28 unbound[48103:0] error: SERVFAIL <chronos3.faa.gov. A IN>: all servers for this domain failed, at zone faa.gov. no server to query nameserver addresses not usable Mar 26 13:41:28 unbound[48103:0] reply: 24.199.82.210 chronos3.faa.gov. A IN SERVFAIL 0.000000 0 34 local/etc/unbound% local/etc/unbound% grep "\.faa\.gov" unbound.log | grep "all server" | wc -l 1408 -- T.Suzuki -- T.Suzuki / E.F.シューマッハーとI.イリイチを読もう