Railway Identity Security: When Attackers Use Valid Access

An intrusion can begin with valid access rather than a visible malware payload. This railway episode frames identity as an operational security boundary. Related CUP episodes: Railway OT Segmentation: When a Network Change Opens the Boundary Zero Trust in OT: Secure Access Beyond the HMI Railway API Security: When Authenticated Data Contradicts Reality Legacy VPNs in OT: Remote Access and the Cost of Disruption OT Remote Access: Closing the Path When the Work Ends OT Session Hijacking: Revoking Trusted Engineering Access OT Session Theft: When a Token Bypasses the Jump Host AiTM Phishing: Why MFA Does Not Prevent Session Theft Control Plane Security: When Network Segmentation Is Rewritten OT Remote Access: Securing the Path to Physical Control