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We had some ransomware get into our system a couple of weeks ago, and it has encrypted a large amount of our files.
I am wondering, is it possible to figure out an encryption key if I know the decrypted content of a file. We have a couple of .txt files that only held a serial number for a specific software product. If I know the original content (the serial) and have the encrypted file, can that be used to find the encryption key and theoretically decrypt all our other files?