How Russian agents hacked 500 million Yahoo users

It was June 2013, and U.S. law enforcement thought they were finally getting their hands on a slippery target: Russian hacker Alexsey Belan, indicted in Nevada and California for computer intrusions at three U.S. e-commerce companies, had been arrested in Europe.

Instead, Belan escaped to Russia, where the U.S. charges didn’t hamper his job prospects.…