North Korean agents pretending to be IT guys have funneled up to $1 billion into Kim Jong Un’s nuclear program

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 to a packed crowd of researchers, executives, and government employees: That trick no longer works. "Do not [ask why] Kim Jong-un is so fat," SttyK warned in all-caps on a presentation slide. "They all notice what you guys have noticed and improved their opsec [operation security]." It might sound far-fetched—like the plot of a Cold War-era spy movie—but the scheme is all too real, according to the FBI and other agencies, as well…