Sony has revealed another attempt to break into its Sony Entertainment Network, PlayStation Network and Sony Online Entertainment services, just months after a major hack exposed up to 100 million customers' details.
The electronics giant's chief information security officer, Philip Reitinger, explained in a blog post that the firm had detected attempts to test a large set of sign-in IDs and passwords against its network database.
"These attempts appear to include a large amount of data obtained from one or more compromised lists from other companies, sites or other sources," he added.
"In this case, given that the data tested against our network consisted of sign-in ID-password pairs, and that the overwhelming majority of the pairs resulted in failed matching attempts, it is likely the data came from another source and not from our networks."
Less than 0.1 per cent of the Japanese firm's customers may have been affected, he explained. Sony has temporarily locked 93,000 accounts globally where the attackers managed to verify the sign-in IDs and passwords with the Sony network database.
"Only a small fraction of these 93,000 accounts showed additional activity prior to being locked," said Reitinger.
"We are currently reviewing those accounts for unauthorised access, and will provide more updates as we have them. Please note, if you have a credit card associated with your account, your credit card number is not at risk."
Sony is requiring secure password resets for any account holders where the attackers managed to verify log-in details against the Sony database.
"We encourage you to choose unique, hard-to-guess passwords and always look for unusual activity in your account," he said.
In April, Sony suffered the first in a long line of attacks on its networks, which exposed the details of up to 100 million customers of its PlayStation Network, Qriocity and Sony Online services, contributing to a $3bn loss in the last financial year.
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