The vast majority of spam (83 per cent) is linked to sites established through ten domain name registrars, according to a new study.

An analysis of junk mail messages by anti-spam firm Knujon ("no junk" spelled backwards) found that while there are 900 accredited domain name registrars, spammers register their spamvertised domains though only a tiny sample.

Knujon's study names and shames the registrars who are contributing (unwittingly or not) to the junk mail problem.

XinNet Cyber Information Company Limited eNom Network Solutions Register.com Planet Online Regtime Ltd. OnlineNIC Inc. Spot Domain LLC Wild West Domains Hichina Web Solutions

Registrars made the list based on factors including: the number of reported illicit domains registered through a registrar, the number of spam messages associated with those domains, and the percentage of dodgy domains within a registrar's total portfolio.

Knujon aims to convince registrars to clean up their act and dismantle spam sites. It reckons that registrars appearing on the list are unlikely to be "criminal or evil", but simply lacking in "effective controls and good policy". Registrars may lack adequate abuse staff or awareness of the problem, it adds.

At least part of the problem is caused by slack or unscrupulous resellers.

The list published by Knujon on Wednesday marks the second time the anti-spam outfit has looked into the domain registration aspect of the wider junk mail problem.

Second take

Knujon's first list, released in May 2008, also featured XinNet at the head of the chart. Beijing Innovative Networks and Joker, second and fourth on the earlier list, were issued breach notices by ICANN. Faced with the warning of having their accreditation pulled, both cleaned up their act.

Dynamic Dolphin has dropped off the lists following successful lawsuits against notorious spammer Scott Richter. Directi, which charted at number nine last time around but no longer makes Knujon's blacklist, probably made it onto the May list largely because of a contract with EstDomains.

Only XinNet (top of the chart) and eNom, Inc (up from fifth to second) make both editions of Knujon's list. "Neither company responded to this report, nor did they take verifiable steps to curb the cited abuses," Knujon states. "In the case of XinNet, their numbers were much worse than Beijing Innovative Networks, but for reasons unknown to us they were not issued a breach notice by ICANN even though we recommended it."

According to the latest figures from Knujon, XinNet harboured 9,346 dodgy domains that threw out an average of 345 spam messages, while eNom was home to 32,610 ropey websites that spewed out an average of 39.7 junk mail messages.

Abused domains represent 0.9 per cent of XinNet's portfolio. Quizzed by Brian Krebs of the Washington Post's Security Fix blog , XinNet stated it tries its best to "suspend all the sites which [are] abused by spammers".

The Waledec worm reportedly makes exclusive use of domain registered through XinNet, but the Chinese firm failed to explain how it planned to tackle that issue in its response.

eNom and Spot Domain, two registrars named in the latest edition of the list, both questioned Knujon's methodology and the reliability of its data. ®