Israeli startup Cylus is developing technology to protect railway and metro systems from cyber-attack. Its solution enables rail companies to detect cyber-attacks in their operational network (including signaling systems and rolling stocks) and block attackers before they can cause any damage.

http://nocamels.com/2018/01/israeli-startup-raises-close-to-5m-to-protect-train-metro-systems-from-cyber-attacks/

https://cylus-security.com/