Content-centric networking (CCN) is one of candidates being spotlighted as the technologies of the future Internet to solve the problems of the current Internet. Since DoS/DDoS attack is the most serious threat to the current Internet, this letter introduces the possibility of DoS/DDoS attack on CCN for the first time. And we introduce an attack method using fake-request packets and propose countermeasures in order to detect and/or react to CCN DoS/DDoS attack, and then analyze the result of our proposal.