More than 453,000 login credentials apparently originating from the Yahoo Voices platform were posted to the hacker site D33D, with the hackers saying they intended the data dump to be a "wake-up call," CNET.com reported Thursday.
"We hope that the parties responsible for managing the security of this subdomain will take this as a wake-up call, and not as a threat," the hackers said in a comment posted along with the hacked date.
"There have been many security holes exploited in Web servers belonging to Yahoo! Inc. that have caused far greater damage than our disclosure. Please do not take them lightly."
Yahoo has confirmed it is investigating the breach.
"We are currently investigating the claims of a compromise of Yahoo! user IDs," it said in a statement.
The breach is the latest in a string of password thefts, with sites such as LinkedIn, eHarmony and Last.fm having been victims of hacking that exposed confidential user information.
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