Fast correlation attack on stream cipher ABC v3

ABC v3 is a stream cipher proposed as a candidate to ECRYPT Estream Project which enters the second evaluation phase. Its key length is 128 bits. In this paper, We show that, there are at least 2103.71 weak keys among 2128 random primary keys, and for each weak key, the expanded key can be recovered with about 233.6 keystream words and 250.56 operations. The attack can be applied to ABC v1 and v2 to retrieve the expanded key generated by a weak key with the same complexity, but the number of weak keys is about 297 + 295.29 . It reveals that ABC v3 incurs more weak keys than that of ABC v1 and v2.

• Type: Journal
• Year: 2008
• Where: CHINAF
• Authors: Haina Zhang, Lin Li, Xiaoyun Wang
• Keywords: CHINAF 2008, Key Length, Random Primary Keys, Weak Keys