Yahoo warns users that their email accounts may have been hacked, again

For the third time in less than six months, Yahoo is warning users that their email accounts may have been hacked.

In December the Internet giant confirmed that a data breach back in 2013 had put a billion users' accounts at risk. The company also said at the time that the incident was believed to be completely separate from the hack Yahoo reported in September, which involved 500 million accounts.

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