Millions of internet-facing devices -- from home broadband routers to industrial equipment -- are still sharing well-known private keys for encrypting their communications, reports The Register. From the report: This is according to research from SEC Consult, which said in a follow-up to its 2015 study on security in embedded systems that the practice of reusing widely known secrets is continuing unabated. Devices and gadgets are still sharing private keys for their builtin HTTPS and SSH servers, basically. It is not difficult to extract these keys from the gizmos and use them to eavesdrop on encrypted connections and interfere with the equipment: imagine intercepting a connection to a web-based control panel, decrypting it, and altering the configuration settings on the fly. And because so many models and products are using the same keys, it's possible to attack thousands of boxes at once. SEC Consult senior security consultant Stefan Viehbock scanned the public internet and found that the practice of using known private keys has increased over the past nine months, with the number of net-accessible vulnerable devices ballooning to more than 4.5 million network appliances, IoT devices, and embedded systems around the world. That's up 40 per cent, or 1.3 million, from November, according to SEC Consult.