*) English thorough explanation are in below:
The above domains are top list of japanese spam mails source in Aug 2011.
Can't easily blocked by FQDN or MX check since the domains was registered properly with a good reputation.
Those domains are alive now and agressively sending spams to mobile and PC mail rapidly, and ONLY in Japanese format.
Japanese spams is working in the different scheme compare to the worldwide malvertising/spambot scheme, I hope the below explanation will make you understand about what happen locally here.
1) The samples of the most detected spam scheme;
The adult advertisement
The adult advertisement using the direct introduction
The money scams
2) How these spams can get through the FQDN/Reputation filtering systems?
The domain is maintaining the reputation, spammers keep on registering new domain and keep on maintaining new domain in daily to weekly basis. By having the good reputation (i.e. new domain) they can spam much in a shot, and that's the target. If the repoutation got corrupted the domain will be switched into new one in no time. It is indeed a clever scheme which cost effort and expertise from spammer side in Japan.
Below is the sample of one domain reputation which was just updated today:
The real problem of these spam scheme is, 1) they are using the user's mail address database which is exchanged in the black market in Japan. 2) Why bother to buy the mail address database? Because for each mail which clicked by the user the point goes to the spammer which can be exchanged with money in the real life.., yep, money boost the this scams, which not a crime act yet.
3) The "legendary" ASN access of these domains;
Have to admit the japanese spams is arranged well for its distribution using the popular registrant for the flexibility and widely access range. Below is the sample of the routing/ASN base info for one of them;
I've seen the similar pattern of this info for 3years now, yet there is nothing that we can do from the networking side to battle this further..
One thing is for sure, we need the law base act for spams too for sure.
4) What is the moral of this story?
*) To fight spams, you need to kill the cycle which boost it. Stop its money flow!
*) To actually stop a spam circulation instantly the law backbone also needed badly, that can be done since the ground of the law can be build (forgery, privacy flaw, money scams, etc)
アドリアン・ヘンドリック (Hendrik ADRIAN)
Sponsored by: 株式会社ケイエルジェイテック