(NEW YORK) -- Yahoo announced Thursday that the usernames and passwords of some email users have been stolen and used to gather personal information. "Recently, we identified a coordinated effort to gain unauthorized access to Yahoo Mail accounts. Upon discovery, we took immediate action to protect our users, prompting them to reset passwords on impacted accounts," the company said Thursday on its blog.
There is currently no evidence, says Yahoo, that the user information was obtained directly from the company's systems, as those investigating the issue believe the information was "likely collected from a third-party database compromise."
There's no word yet on how many accounts have been affected, but identity theft expert Robert Siciliano says it's roublesome news for Yahoo's millions of users.
"Once a criminal hacker gets access to your email, he can easily reset the passwords for a number of your other accounts," he said.
In the meantime, Yahoo says they are using a second sign-in verification to allow users to re-secure their accounts. Impacted users, the company says, will be prompted to change their password and may even receive an email notification or mobile text message if they've added a mobile phone number to their account.
There are almost 300 million Yahoo email accounts across the world, including 81 million in the U.S.
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