TY - JOUR AU - Shen, Yaobin AU - Wang, Lei PY - 2019/06/11 Y2 - 2024/03/29 TI - On Beyond-Birthday-Bound Security: Revisiting the Development of ISO/IEC 9797-1 MACs JF - IACR Transactions on Symmetric Cryptology JA - ToSC VL - 2019 IS - 2 SE - Articles DO - 10.13154/tosc.v2019.i2.146-168 UR - https://tosc.iacr.org/index.php/ToSC/article/view/8317 SP - 146-168 AB - <p>ISO/IEC 9797-1 is an international standard for block-cipher-based Message Authentication Code (MAC). The current version ISO/IEC 9797-1:2011 specifies six single-pass CBC-like MAC structures that are capped at the birthday bound security. For a higher security that is beyond-birthday bound, it recommends to use the concatenation combiner of two single-pass MACs. In this paper, we reveal the invalidity of the suggestion, by presenting a birthday bound forgery attack on the concatenation combiner, which is essentially based on Joux’s multi-collision. Notably, our new forgery attack for the concatenation of two MAC Algorithm 1 with padding scheme 2 only requires 3 queries. Moreover, we look for patches by revisiting the development of ISO/IEC 9797-1 with respect to the beyond-birthday bound security. More specifically, we evaluate the XOR combiner of single-pass CBC-like MACs, which was used in previous version of ISO/IEC 9797-1.</p> ER -