The penalty, which was levied by the UK Information Commissioner's Office last week, suggests that the attack could have been prevented if the electronics and gaming giant had kept its software up to date and followed best practices for protecting passwords.
"If you are responsible for so many payment card details and log-in details then keeping that personal data secure has to be your priority," said David Smith, Deputy Commissioner and Director of Data Protection at the ICO, in a written statement. "In this case, that just didn't happen. And when the database was targeted – albeit in a determined criminal attack – the security measures in place were simply not good enough.
"There's no disguising that this is a business that should have known better," Smith stated. "It is a company that trades on its technical expertise, and there's no doubt in my mind that they had access to both the technical knowledge and the resources to keep this information safe.
"The penalty we've issued today is clearly substantial, but we make no apologies for that," the statement says. "The case is one of the most serious ever reported to us. It directly affected a huge number of consumers, and at the very least put them at risk of identity theft."
In a redacted version of its monetary penalty notice published last week, the ICO noted that Sony had been attacked by hackers several times previous to the distributed denial-of-service attack that resulted in the data loss in question.
"Therefore, the data controller [Sony] should have anticipated a further attack on its systems and taken appropriate security measures," the notice states. "Instead, the data controller was storing vast amounts of personal data," including financial information, on its systems, the ICO says.
Sony plans to appeal the penalty, according to news reports.
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