Expected behavior violation in the in-vehicle network of the Indian Motorcycle Scout Bobber + Tech 2025 model year allows an adjacent-network attacker to bypass the motorcycle's anti-theft shutdown by forcing the Wireless Control Module (WCM) into the CAN bus-off state. Using a well-known CAN error-frame injection technique against a periodic WCM transmission, the attacker drives the WCM CAN controller's transmit error counter past the bus-off threshold, after which the WCM stops transmitting all messages, including the shutdown command. Peer ECUs do not interpret WCM silence as a security event and continue normal operation, allowing the motorcycle to be operated despite the immobilizer never having been unlocked. Specific protocol details have been withheld pending vendor remediation.
Treat absence of the WCM heartbeat as a security event in peer ECUs — command shutdown if the WCM's periodic message is missing beyond a bounded interval. Authenticate the heartbeat with AUTOSAR SecOC or equivalent to prevent post-silence spoofing. Auto-recover the WCM from bus-off and log the event.