A muffled voice in an innocuous YouTube video could issue commands to a nearby smartphone without you even knowing it. The researchers describe the threat in a research paper to be presented next month at the USENIX Security Symposium in Austin, Texas. The result condenses the words into a demonic growl, but software can still be programmed to react to the sound. Voice recognition has taken off quickly on phones, thanks to services like Google Now and Apple’s Siri, but voice software can also make it easier to hack devices.”]