Hackers have put up for sale the details of 2.2 million credit cards allegedly obtained in the massive data breach of Sony’s Playstation Network, a top security researcher said Friday.

Kevin Stevens of Trend Micro said on Twitter that unidentified hackers were asking 100,000 dollars for a database containing the stolen financial information.

“The hackers that hacked PSN are selling off the DB (database),” Stevens wrote. “They reportedly have 2.2 million credits cards with CVVs,” he added, referring to the three-number security code on the back of the cards.

Stevens said that he tracked chatter about the sale offer on underground chat networks used by hackers. But he noted that he had not seen the database and that it was possible that hackers were just bragging.

Sony claimed Thursday that all credit card information on the site was encrypted and that it had never requested the CVV numbers of card holders. It said that while it was possible that the credit card info had been stolen in the network breach, the company had not seen any evidence that the data was taken.

The noted technology website ArsTechnica reported that there had already been a surge in the number of members of the Playstation network who reported fraud on their credit cards.

The network intrusion occurred last week, but Sony waited until Monday to inform users that the unidentified hacker had gleaned the personal details of the network’s 77 million accountholders. A class-action suit against the company was filed on Wednesday in California.

Analysts said the security imbroglio is likely to damage Sony’s plans to expand the network into a full-blown content network linking televisions, computers, consoles and other devices into an entertainment ecosystem capable of challenging Apple’s iTunes and Netflix.com.