College student hacks Taiwan high-speed rail line with software-defined radios, stopping four trains — 19 years without crypto key rotation ends in predictable result as hacker sails through 7 layers of protection

A 23-year-old student in Taiwan allegedly used a software-defined radio setup to spoof a high-speed rail emergency alarm.

The false alert forced manual braking and stopped four trains for 48 minutes before investigators traced the signal to his home.

The case exposes weak, long-unchanged TETRA security keys and broader vulnerabilities in critical transport communications.