Sony said that it expects the cleanup cost from the data breaches it's suffered to cost at least $171 million. Sony said the data breach costs will affect revenues for its fiscal 2011 year, which ends on March 31, 2012.

According to a statement released by Sony's investor relations group, "based on information currently available to Sony, our currently known costs associated with the unauthorized network access are estimated to be approximately 14 billion yen," or about $171 million.

But according to an InformationWeek article, those costs could go much higher, the company warned investors during a call on Monday. "So far, we have not received any confirmed reports of customer identity theft issues, nor confirmed any misuse of credit cards from the cyber-attack. Those are key variables, and if that changes, the costs could change," said Sony, as reported by Joystiq, which saw a transcript of the call.

On Sunday, new revelations surfaced that Sony apparently also suffered another data breach earlier this month, after hackers cracked Sony BMG's website in Greece, the InformationWeek report said, adding that would make it the seventh data breach suffered by Sony since April 2011.

In this breach, which occurred on May 5, said the report, attackers obtained information about more than 8,000 website users, according to The Hackers News, which received a copy of the website's SQL database from "b4d_vipera," the hacker who took responsibility for the breach.

The attacker also leaked a sample of the purloined database--containing 450 records--to Pastebin. It contains usernames, passwords for the Sony website, and email addresses. The InformationWeek article says that security experts recommend that anyone with a Sony BMG account in Greece immediately change their Sony password, and any other uses of the same password online.