Exercise $3$

Name:

$($Another malleability example$).$ Let us give another example illustrating the malleability of stream

ciphers. Suppose you are told that the stream cipher encryption of the message $$attack at dawn" is

$6$c$73$d$5240$a$948$c$86981$bc$294814$d $($the plaintext letters are encoded as $8-$bit ASCII and the given

ciphertext is written in hex$).$ What would be the stream cipher encryption of the message $$attack at

dusk" under the same key?