Millions of embedded devices, including home routers, modems, IP cameras, VoIP phones, are shareing the same hard-coded(Secure Shell) cryptographic keys or(HTTP Secure) server certificates that expose them to various types of malicious attacks. If you are able to access one device remotely, you can possibly log into hundreds of thousands of other devices including the devices from different manufacturers. At least 230 crypto keys are actively being used by more than 4 Million IoT devices, the researchers found.
Source: https://thehackernews.com/2015/11/iot-device-crypto-keys.html