UK Security Researcher Pulls Handbrake on Global Ransomware Menace A U.K.-based cyber researcher known as MalwareTech stopped the WannaCry ransomware that gained control of thousands of computers worldwide, forcing victims to pay $300 in bitcoin to restore their files. WannaCry was able to exploit a Windows vulnerability leaked in April and use a hacking tool believed to be stolen from the National Security Agency (NSA). The ransomware spread across 75,000 PCs, including 48 hospitals in the U.K.   Accidental Fix…