Increasing threats and rising attack vectors lead to an enhanced assessments of IT/OT security in the approval process of railway systems. Our Head of Railway Security Research, Prof. Stefan Katzenbeisser, is conducting the necessary appraisal of the pre-series project DSTW Mertingen-Meitingen. For this purpose, he was appointed as the first inspection expert for IT security in the domain of CCS (command, control and signalling) by the German Railway Authority (EBA).