DNS/KnotResolver/brau.jp/soaについて、ここに記述してください。
手元にKnot Resolver 5.1.2 があるので、試す。 127.0.0.1, mode("permissive")
default(normal)では毒は入らない。-- ToshinoriMaeno 2020-08-27 01:55:55
1. キャッシュからの返答
$ dig -t soa brau.jp @127.0.0.1 ; <<>> DiG 9.16.1-Ubuntu <<>> -t soa brau.jp @127.0.0.1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 58693 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;brau.jp. IN SOA ;; ANSWER SECTION: brau.jp. 2408 IN SOA ns.brau.internat.jp. hostmaster.brau.jp. 1598366138 16384 2048 1048576 2560 ;; Query time: 0 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: 木 8月 27 10:37:21 JST 2020 ;; MSG SIZE rcvd: 105
2. 本来のSOA
$ dig -t soa brau.jp @150.42.6.4 ; <<>> DiG 9.16.1-Ubuntu <<>> -t soa brau.jp @150.42.6.4 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3934 ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2 ;; WARNING: recursion requested but not available ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 512 ;; QUESTION SECTION: ;brau.jp. IN SOA ;; ANSWER SECTION: brau.jp. 120 IN SOA ns.brau.jp. tss.e-ontap.com. 2020082501 3600 600 86400 60 ;; AUTHORITY SECTION: brau.jp. 180 IN NS ns.brau.jp. ;; ADDITIONAL SECTION: ns.brau.jp. 120 IN A 150.42.6.4 ;; Query time: 7 msec ;; SERVER: 150.42.6.4#53(150.42.6.4) ;; WHEN: 木 8月 27 10:39:23 JST 2020 ;; MSG SIZE rcvd: 120
3. 毒入返答
偽サイトからの返事
$ dig -t soa brau.jp @150.42.6.9 ; <<>> DiG 9.16.1-Ubuntu <<>> -t soa brau.jp @150.42.6.9 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 21731 ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1 ;; WARNING: recursion requested but not available ;; QUESTION SECTION: ;brau.jp. IN SOA ;; ANSWER SECTION: brau.jp. 2560 IN SOA ns.brau.internat.jp. hostmaster.brau.jp. 1598366138 16384 2048 1048576 2560 ;; AUTHORITY SECTION: brau.jp. 60 IN NS ns.brau.internat.jp. ;; ADDITIONAL SECTION: ns.brau.internat.jp. 60 IN A 150.42.6.9 ;; Query time: 7 msec ;; SERVER: 150.42.6.9#53(150.42.6.9) ;; WHEN: 木 8月 27 10:40:51 JST 2020 ;; MSG SIZE rcvd: 119