@techreport{oai:ipsj.ixsq.nii.ac.jp:00227070,
 author = {芝山, 直喜 and 五十嵐, 保隆 and Naoki, Shibayama and Yasutaka, Igarashi},
 issue = {63},
 month = {Jul},
 note = {LBC-3 は 2022 年に Nyssanbayeva らによって提案された 64 ビットブロック暗号であり，鍵長は 80 ビット，ラウンド数は 20 である．これまでに提案者による avalanche effect の評価，安士らによる差分攻撃及び線形攻撃耐性評価が行われているが，高階差分攻撃に対する耐性は未知である．本稿では，LBC-3 の新しい高階差分特性について報告する．具体的には，LBC-3 には 18 ラウンドの 60 階差分特性が存在することがわかった．また，この特性を利用したフルラウンドの LBC-3 に対する高階差分攻撃の結果を述べる．, LBC-3 is a block cipher proposed by Nyssanbayeva et al. in 2022. The block size is 64-bit, the secret size is 80-bit, and the recommended number of rounds is 20, respectively. The designer evaluated its security using the avalanche effect, and Yasushi et al. evaluated the security against differential cryptanalysis and linear cryptanalysis. On the other hand, it has not been reported the security against higher order differential cryptanalysis. This paper shows a higher order differential of LBC-3. By the computer experiment, we found a new 12-round characteristic using 28-th order differential. Then, we also show a new 18-round characteristic using 60-th order differential which is a 6-round extension of the 12-round one to the direction to plaintext theoretically. By exploiting this characteristic, the full-round LBC-3 can be attacked with 261.6 blocks of chosen plaintext and 261.6 times of data encryption.},
 title = {ブロック暗号LBC-3の高階差分特性},
 year = {2023}
}