Sonic Drive-In, the fast food restaurant chain, is offering free fraud detection and identity theft protection following a security breach at some of the fast food restaurant chain's locations.KrebsOnSecurity broke news of the breach about a week ago, but Sonic Drive-In didn't offer a detailed statement about next steps until today. The statement was briefly delayed amid an ongoing law enforcement investigation. Third-party forensics teams have also been involved, the company said.Credit and debit card numbers may have been acquired without authorization as part of a malware attack experienced at certain Sonic Drive-In locations, the company said. The Sonic statement also included multiple apologies to customers, but was vague in terms of the breach's size and associated malware.