Related Key Cryptanalysis of the LEX Stream Cipher
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چکیده
LEX is a stream cipher proposed by Alex Biryukov. It was selected to phase 3 of the eSTREAM competition. LEX is based on the Advanced Encryption Standard (AES) block cipher and uses a methodology called ”Leak Extraction”, proposed by Biryukov himself. In this paper, we cryptanalyze LEX using two related keys. We have mounted a key recovery attack on LEX, which using 2 key streams yields a complete round key with 2 operations. This improves the existing best cryptanalysis of LEX which needs 2 operations to ascertain the key.
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تاریخ انتشار 2010