WannaCry

WannaCry is a worm-type ransomware that spread from 12 May 2017 by exploiting the EternalBlue vulnerability in Windows SMBv1, an exploit developed by the NSA and released by the Shadow Brokers group weeks earlier. Unlike conventional ransomware requiring human interaction, WannaCry spreads autonomously from machine to machine across networks whose systems had not applied the MS17-010 patch published by Microsoft in March 2017. Within days, more than 200,000 systems in 150 countries were affected, including the British NHS, Spanish telecoms and car factories in France and Romania. The attack was attributed to the Lazarus group, linked to North Korea, with estimated global economic damage exceeding four billion dollars. For cyber risk models, WannaCry is the canonical example of a wormable attack whose kinetics resemble a digital pandemic: loss correlation is near-perfect across vulnerable networks, making any pooling mechanism inoperative. This attack vector constitutes a reference scenario in most cyber PML models.