Equifax says a "coding issue" is to blame for it providing inaccurate credit scores for millions of Americans.
The firm says the coding issue lasted for three weeks earlier this year and was within a legacy, on-premises server environment that was slated to be migrated to the cloud.
While millions of people were affected, Equifax says that less than 300,000 experienced a score shift of 25 points or more and that credit reports were not changed.
Says a statement: "For those consumers that did experience a score shift, initial analysis indicates that only a small number of them may have received a different credit decision."
Continues the company: "The issue has been fixed, we are working closely with lenders, and we are accelerating the migration of this environment to the Equifax Cloud, which will provide additional controls and monitoring that will help to detect and prevent similar issues in the future."