A Chosen IV Attack Using Phase Shifting Equivalent Keys against DECIM v2.
Hidehiko Nakagami, Teramura Ryoichi, Toshihiro Ohigashi, Hidenori Kuwakado, Masakatu Morii · 2008
Abstract. DECIM v2 is a stream cipher submitted to the ECRYPT stream cipher project (eSTREAM) and ISO/IEC 18033-4. No attack against DECIM v2 has been proposed yet. In this paper, we propose a chosen IV attack against DECIM v2 using a new equivalent key class. Our attack can recover an 80-bit key with a time complexity of 2 79.90 when all bits of the IV are zero. This result is the best one on DECIM v2.