A cybersecurity researcher appears to have discovered a "kill switch" that can prevent the spread of the WannaCry rans

A cybersecurity researcher appears to have discovered a “kill switch” that can prevent the spread of the WannaCry ransomware—for now—that has caused the cyberattacks wreaking havoc globally, they told AFP Saturday.
https://phys.org/news/2017-05-cyberattack-ransomeware.html