In layman’s terms, ransomeware takes commonly used extensions (such as .doc for Microsoft Word, .xls for Microsoft Excel) and encrypts files associated with those extensions, which prevents you from ever accessing those files again (unless you’re lucky and a developer resolves the encryption algorithm) Cybercriminals often provide a link to send money, specifically BitCoins. Once payment is received, they’ll provide a code that can remove the encryption. Some actually follow through; many opine that if cybercriminals followthrough, more people will be more likely to pay. However, you should never pay them; or this behavior will never end.
Ransomware entered the public’s vernacular this summer when the WannaCry ransomeware attack, using an SMB protocol exploit called EternalBlue on unpatched Windows operating systems, propagated the internet. Analysts predicted that the financial cost of WannaCry could surpass $4 billion. Several major companies, especially the European healthcare industry, were hit especially hard. The spread suddenly stopped when a computer security researcher named Marcus Hutchins unexpectedly triggered a “kill switch” by registering a domain name. In an ironic twist, Hutchins was arrested by FBI agents, accused of selling a program called Kronos, “designed to steal online backing credentials.”