On the Boomerang Spectrum of Power Permutation $X^{2^{3n}+2^{2n}+2^n-1}$ over $\GF{2^{4n}}$ and Extraction of Optimal Uniformity Boomerang Functions

Kwang Ho Kim, Sihem Mesnager, Ye Bong Kim

A substitution box (S-box) in a symmetric primitive is a mapping $F$ that takes $k$ binary inputs and whose image is a binary $m$-tuple for some positive integers $k$ and $m$, whic…