Equifax Inc. learned about a major breach of its computer systems in March — almost five months before the date it has publicly disclosed, according to three people familiar with the situation.
In a statement, the company said the March breach was not related to the hack that exposed the personal and financial data on 143 million U.S. consumers, but one of the people said the breaches involve the same intruders. Either way, the revelation that the 118-year-old credit-reporting agency suffered two major incidents in the span of a few months adds to a mounting crisis at the company, which is the subject of multiple investigations and announced the retirement of two of its top security executives on Friday.
Equifax hired the security firm Mandiant on both occasions and may have believed it had the initial breach under control, only to have to bring the investigators back when it detected suspicious activity again on
