Abstract:The extensive use of Information and Communication Technology in critical infrastructures such as Industrial Control Systems make them vulnerable to cyber-attacks. One particular class of cyber-attacks is advanced persistent threats where highly skilled attackers can steal user authentication information's and move in the network from host to host until a valuable target is reached. The detection of the attacker should occur as soon as possible in order to take appropriate response, otherwise the attacker will have enough time to reach sensitive assets. When facing intelligent threats, intelligent solutions have to be designed. Therefore, in this paper, we take advantage of recent progress in deep learning to build a convolutional neural networks that can detect intrusions in cyber physical system. The Intrusion Detection System is applied on the NSL-KDD dataset and the performances of the proposed approach are presented and compared with the state of art. Results show the effectiveness of the techniques.