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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?


marked as duplicate by Xander, Community Jul 10 '15 at 2:05

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No, that is not how encryption works. Where it then you could defeat any Full Disk Encryption by knowing the contents of say some default icon file.

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