MY mother received the ransom note on the Tuesday before Thanksgiving. It popped up on her computer screen soon after she’d discovered that all of her files had been locked. “Your files are encrypted,” it announced. “To get the key to decrypt files you have to pay 500 USD.” If my mother failed to pay within a week, the price would go up to $1,000. After that, her decryption key would be destroyed and any chance of accessing the 5,726 files on her PC — all of her data — would be lost forever.

Sincerely, CryptoWall.

For The New York Times

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