Kmart says it has removed malware that had infected its checkout registers in stores. The company believes the malware may have been in place for about a month before it was detected. Rachel Murray/Getty Images hide caption

itoggle caption Rachel Murray/Getty Images

Kmart's plan to be open for 41 straight hours beginning at 6 a.m. Thanksgiving morning is drawing criticism. At this Kmart store in Connecticut, shoppers wait in line to take advantage of sales on Thanksgiving Day. Douglas Healey/AP hide caption

itoggle caption Douglas Healey/AP