Points: 75

Tags: cryptography 

Poll rating:

We encrypted a flag with AES-ECB encryption using a secret key, and got the hash: e220eb994c8fc16388dbd60a969d4953f042fc0bce25dbef573cf522636a1ba3fafa1a7c21ff824a5824c5dc4a376e75 
However, we lost our plaintext flag and also lost our key and we can't seem to decrypt the hash back :(. 
Luckily we encrypted a bunch of other flags with the same key. Can you recover the lost flag using this?

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