Ransomware attack leads to shutdown of major U.S. pipeline system

Ransomware attacks, in which hackers lock up computer systems — usually by encrypting data — and demand payment to free up the system, are a global scourge. In recent years, they have affected everyone from banks and hospitals to universities and municipalities — almost 2,400 organizations in the United States were victimized last year alone, one security firm reported. But the attackers are increasingly targeting industrial sectors because these firms are more willing to pay up to regain control of their systems, experts say.