Security meltdowns on your smartphone are often self-inflicted: You clicked the wrong link, or installed the wrong app. But for millions of Android devices, the vulnerabilities have been baked in ahead of time, deep in the firmware, just waiting to be exploited. Who put them there? Some combination of the manufacturer that made it, and the carrier that sold it to you.

Get in-depth coverage of current and future trends in technology, and how they are shaping business, entertainment, communications, science, politics, and society.