The U.S. government may not be able to prevent another global cyberattack like WannaCry, a senior cybersecurity official has said. Jeanette Manfra, the assistant director for cybersecurity for Homeland Security’s Cybersecurity and Infrastructure Security Agency (CISA), said on stage at TechCrunch Disrupt SF that the 2017 WannaCry cyberattack, which saw hundreds of thousands of computers…