WASHINGTON (Sputnik) — On Thursday, Yahoo announced that a state-sponsored actor hacked its networks in late 2014, stealing information about some 500 million users.
"User information was first compromised in 2014, yet the company only announced the breach last week. This is unacceptable," the letter stated.
The senators, including Elizabeth Warren, Richard Blumenthal and Patrick Leahy, asked Yahoo to provide a briefing on the company’s investigation into the incident.
Yahoo has previously said it was cooperating with law enforcement agencies concerning the hack.