Demandware says 30 of its clients booked more than $100 million in online sales in 2015, up from 22 a year earlier.
Richard M. Smith, an independent Internet consultant, says he's corresponded with Maxus, the supposed hacker of the CD Universe site.
Maxus allegedly stole as many as 300,000 credit card numbers-from CD Universe, the online music subsidiary of entertainment site eUniverse Inc., then posted the numbers on the Web after the company refused to pay a $100,000 ransom.
EUniverse, Wallingford, Conn., has hired a tech security firm to review its procedures and is working with major credit card companies to limit losses or inconvenience associated with the theft. The FBI also is investigating.
Smith says Maxus told him that he's broken into several other e-commerce sites, stealing credit card numbers to sell on the Internet. Hackers who trade credit card numbers on the Web are known as carders.
Maxus told Smith he's 18 years old and lives in Russia. He uses a Canadian e-mail service, along with various other Web services and proxy servers, Smith says. Maxus told Smith that he has been breaking into Web sites for the past two years.
Maxus claims that he used Cybercash's ICVERIFY software to break into CD Universe. Cybercash has issued a statement insisting that its software was not involved in the incident. A Cybercash spokesperson says CD Universe purchased a copy of ICVERIFY but has not used the program. The spokesperson added that the software could not have been used as Maxus described.
Maxus told Smith he used a copy of ICVERIFY to charge a purchase to a stolen credit card, then issued a refund to his own card. Smith was skeptical about the hacker's description. "I raised an eyebrow," he says.