TMD-Tradeoff and State Entropy Loss Considerations of Streamcipher MICKEY
We give three weaknesses of a recently proposed streamcipher MICKEY. A small class of weak keys is found and we show time-memory-data tradeoff is applicable. We also show that the state update function reduces entropy of the internal state as it is iterated, resulting in keystreams that start out differently but become merged together towards the end.
KeywordsMICKEY stream cipher time memory data tradeoff internal state entropy weak key
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