If your morning routine involves checking Yahoo Mail from your favorite computer, smartphone or tablet, don't be surprised if your breakfast comes with a side of password reset today.
Yahoo announced Thursday that a "coordinated effort to gain unauthorized access to Yahoo Mail accounts" has been detected by its security experts, prompting a mandatory password reset for those affected.
"Based on our current findings, the list of usernames and passwords that were used to execute the attack was likely collected from a third-party database compromise," the Tumblr blog post explains. "We have no evidence that they were obtained directly from Yahoo’s systems.
"Our ongoing investigation shows that malicious computer software used the list of usernames and passwords to access Yahoo Mail accounts," the post continues. "The information sought in the attack seems to be names and email addresses from the affected accounts’ most recent sent emails."
Impacted accounts are being forced to reset passwords using Yahoo's second sign-in verification, and may be notified about the change via SMS text message if they've added a mobile number to their account.
"We regret this has happened and want to assure our users that we take the security of their data very seriously," the blog post concludes, while recommending the generally accepted good practice of not repeating passwords across multiple websites or services.
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