A suspected cyberattack on hardware retailer Home Depot’s nationwide network of stores may be even bigger and impact more consumers than Target’s notorious 2013 data breach. A new report from a well-known security blogger suggests credit card data stolen during the attack is being sold in an online cybercrime store.

Although Home Depot and security firm Symantec are investigating the breach, the retailer appears uncertain who has been affected or how big the impact will be. Pillsbury partner and cybercrime authority Brian Finch told Fox Business that’s why it remains critical for consumers to actively monitor their bank accounts.

“Right now it is a waiting game for Home Depot customers,” he said. “If you are truly concerned you can proactively ask for a new card. Otherwise, just monitor your statements for suspicious activity – which is a good measure regardless of this one event.”