Security researchers are racing to analyze and contain a new form of ransomware that has begun seizing computer networks around the world, just weeks after a similar cyberattack crippled an unprecedented number of businesses and hospitals.Like the massive malware outbreak in mid-May, the new virus also spreads via a flaw in Microsoft Windows originally exposed in a leak of apparent NSA hacking tools, according to researchers.The malicious software, dubbed Petya, has battered organizations in Russia, Ukraine, Spain, France and Poland, according to cybersecurity researchers, sending law enforcement officials scrambling and sparking fears that another global ransomware attack is underway.