In corporate security circles, a ghastly new fear has led to some strange advice for recruiters interviewing potential IT staffers: Ask the candidate to insult North Korea’s Supreme Leader, Kim Jong-un. The idea is that if the interviewee is a North Korean agent posing as a regular candidate, he’ll be visibly thrown off, outing himself. But at a cybersecurity conference in Las Vegas this August, an analyst wearing a black hoodie and dark glasses who goes by “SttyK” broke some disappointing news ...