An intruder stole login credentials from the companys point-of-sale vendor and used these credentials to remotely access the point of sale systems at some corporate and franchised locations between June 16, 2014 and Sept. 5, 2014. There are more than 1,900 franchised Jimmy John’s locations across the United States, meaning this breach impacted roughly 11 percent of all stores. The company has posted a listing on its Web site jimmyjohns.com of the restaurant locations affected by the intrusion.”]
Source: https://krebsonsecurity.com/2014/09/jimmy-johns-confirms-breach-at-216-stores/