The home improvement chain also said the malware responsible for the breach has been removed from all stores.
Internet and law enforcement officials suspect many computers were hijacked to launch denial of service attacks that have disrupted popular e-commerce sites in recent days. Early indications have led officials to believe the attacks have come from inside the United States.
Jed Picket, a technician at the CERT Coordination Center, a federally funded research center at Carnegie Mellon University that tracks security breaches on the Internet, says experts still can find no pattern on the nature of the attacks.
The attacks should be a warning that Web sites need an alternative channel, such as a toll-free phone number, to be used when sites are down, says Cormac Foster, an analyst at Jupiter Communications, New York. "It may not be the Web site's fault that they are down--no site is bullet-proof, " he adds. "But they need to have an alternate plan."
Foster also predicted that the attacks, a relatively simple hack, will pass when the novelty for the hackers wears off.