Cybersecurity journalist Brian Krebs said the home improvement company could be the source of a massive new batch of stolen debit and credit cards.
In a statement to Krebs, Home Depot spokeswoman Paula Drake said: "'Protecting our customers' information is something we take extremely seriously, and we are aggressively gathering facts at this point while working to protect customers.'"
Krebs also said the breach may go back to late April or early May. If true, could be even larger than the breach at Target stores that affected 40 million customers credit and debit cards late last year.
The company said they will alert customers as soon as it can once they confirm a breach has happened.