The XKW7 wasn't smart. That was its genius. Factory floors loved it because it had no IP stack, no web interface, no "cloud." Pure, dumb, packet-switching reliability. But Dina had noticed an anomaly three weeks ago—intermittent latency spikes in a textile mill’s network that correlated with a ghost MAC address. The only common denominator? An XKW7 buried in a junction box.

Outside, the city's power grid hummed with a billion tiny conversations—light switches, chargers, appliances—each one a potential ear. Dina looked at her own desktop switch. Port 4's LED blinked. Friendly. Steady.

Someone had installed a inside the switch's own voltage regulator circuit. It had no wireless radio, no outbound connection. It simply modulated the existing electrical noise of the switch's power supply. Any device sharing the same unshielded power circuit—a PLC, a camera, even a cheap phone charger—could demodulate that noise and exfiltrate packets bit by bit.

She decapped the mystery IC under a microscope. Laser-etched on the die, barely visible: XK-SEC/7 . A custom chip. She cross-referenced supply chains—the XKW7 batch was from a contract manufacturer that had gone bankrupt six years ago. But six months before that bankruptcy, a shell company had ordered 5,000 modified voltage regulators.

Leon stared at her final report. "So how do we fix it?"