02 Oct Encryption Mode – Corrupted Cipher Text
To understand the properties of various encryption modes, we would like to do the following exercise:
1. Create a text file that is at least 64 bytes long.
2. Encrypt the file using the AES-128 cipher.
3. Change exactly 1 bit in the encrypted output using a hex editor.
4. Decrypt the corrupted file (encrypted version) using the correct key and IV.
Submit: Please answer the following questions:
What information can you recover by decrypting the corrupted file, if the encryption mode is ECB, CBC, CFB, or OFB, respectively?
Please explain why for each algorithm in the previous step.
What are the implications of these differences?
Note:
Please explain each step: ECB, CBC, CFB, or OFB
