The hacked users included an assistant to the deputy chairman of Russia, an officer in Russia's Ministry of Internal Affairs and a trainer working in Russia's Ministry of Sports. Others belonged to Russian journalists, officials of states bordering Russia, U.S. government workers, an employee of a Swiss Bitcoin wallet company and a U.S. airline worker.
So clinical was the attack that when Yahoo first approached the FBI in 2014, it went with worries that 26 accounts had been targeted by hackers. It wasn't until late August 2016 that the full scale of the breach began to become apparent and the FBI investigation significantly stepped up.
In December 2016, Yahoo went public with details of the breach and advised hundreds of millions of users to change their passwords.
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