Smart devices like Nest getting hacked in digital home invasions

Arjun Sud sits with his wife, Jessica, and 7-month-old son, Oliver, at their home in Lake Barrington. (Erin Hooley/Chicago Tribune/TNS)

Arjun and Jessica Sud routinely use a baby monitor to keep tabs on their seven-month-old's bedroom. Last month, they heard something chilling through the monitor: A deep male voice was speaking to their child.

"Immediately I barge into the room because I'm like, 'Oh my God, maybe someone got in there'," said Arjun Sud, 29. "The moment I walk in, it's quiet."