Yahoo warns users that hackers have broken into its mail service. It is not known how many accounts are involved. The hackers allegedly extracted account names and passwords from a third-party database.
Yahoo speaks of a “coordinated effort to gain unauthorized access to Yahoo Mail accounts.” The US company does not provide details about the hack. The company says it has no indications that its own systems have been invaded. The malicious parties would have been after email addresses with which Yahoo users mail the most.
After investigation, Yahoo concludes that the list of usernames and passwords used in the attack came from a third-party database. Users of accounts that are affected must set a new password. Yahoo says it is working with law enforcement to track down the perpetrators and has taken unspecified measures to increase security.