What exactly does WannaCry do?
RansomWare like WannaCry works by encrypting most or even all of the files on a user's computer. Then, the software demands that a ransom be paid in order to have the files decrypted. In the case of WannaCry specifically, the software demands that the victim pays a ransom of $300 in bitcoins at the time of infection. If the user doesn't pay the ransom without three days, the amount doubles to $600. After seven days without payment, WannaCry will delete all of the encrypted files and all data will be lost.
Source: bgr. com
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