Explore the potential security risks of IoT devices in densely populated urban areas through this IEEE Symposium presentation. Delve into a case study involving Philips Hue smart lamps to understand how a worm can spread rapidly using ZigBee wireless connectivity and physical proximity. Learn about the critical mass of devices needed for a chain reaction, techniques for exploiting vulnerabilities in the ZigBee Light Link protocol, and methods for extracting encryption keys. Gain insights into the challenges of securing IoT devices, even for large companies using standard cryptographic techniques. Examine the implications of this research for future IoT security and urban infrastructure protection.