We investigate S-boxes defined by pairs of Orthogonal Cellular Automata (OCA), motivated the fact that such CA always define bijective vectorial Boolean functions, and could thus be interesting for design block ciphers. In particular, we perform an exhaustive search all nonlinear OCA diameter $$d=4$$ $$d=5$$ , which generate size $$6\times 6$$ $$8\times 8$$ respectively. Surprisingly, these tur...