Cipher Feedback Mode (CFB) is an encryption mode, that builds a self-synchronizing stream-cipher from a block-cipher.

Cipher Feedback Mode (CFB) turns a block-cipher into a stream cipher by generating a keystream using the block-cipher that is XORed with the plaintext to produce the ciphertext. CFB mode feeds back the ciphertext block as the next input of the block-cipher to create successive keystream blocks.

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