On September 7, 2017, Equifax announced a cybersecurity incident affecting 143 million consumers. This number eventually grew to 148 million—nearly half the U.S. population and 56 percent of American adults. This staff report explains the circumstances of the cyberattack against Equifax, one of the largest consumer reporting agencies (CRA) in the world.

https://oversight.house.gov/wp-content/uploads/2018/12/Equifax-Report.pdf