Cryptanalysis of the Stream Cipher ABC v2
نویسندگان
چکیده
ABC v2 is a software-efficient stream cipher with 128-bit key. In this paper, we apply a fast correlation attack to break ABC v2 with weak keys. There are about 2 weak keys in ABC v2. The complexity to identify a weak key and to recover the internal state of a weak key is low: identifying one weak key from about 2 random keys requires 6460 keystream bytes and 2 operations for each random key. Recovering the internal state of a weak key requires about 2 keystream bytes and 2 operations. A similar attack can be applied to break ABC v1 with much lower complexity than the previous attack on ABC v1.
منابع مشابه
Cryptanalysis of ABC v2
ABC v2 is a stream cipher with 128-bit key. In this paper, we show that there are about 2 weak keys. The complexity to identify each weak key and to recover the internal state is low. To identify a weak key from about 2 random keys, we need 2 keystream bytes from each key, and 2 operations are required for each keystream. Recovering the internal state of a weak key requires about 2 keystream by...
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