WannaCry Example: A 2017 worldwide cyberattack by the WannaCry ransomware cryptoworm, which targeted computers running older Microsoft Windows operating systems. WannaCry encrypted data and demanding ransom payments in Bitcoin to decrypt files. Microsoft had released patches previously to close the exploit, but all of the systems that were attacked had not installed the update that would close the exploit. The attack was stopped within a few days of its discovery due to emergency patches released by Microsoft. The attack was estimated to have affected more than 200,000 computers across 150 countries, with total damages ranging from hundreds of millions to billions of dollars.