Abstract
Kaon decays allow to probe hidden sectors by searching for new particles that can be feebly coupled
to the Standard Model sectors via neutrino, vector or scalar portals. Recent results and prospects of
such searches at NA62 are presented. In particular, search for the heavy neutral lepton (N) production
in K to mu N decay (neutrino portal) , dark photon, search in K to pi pi0, pi0 to A gamma (vector
portal) and inflaton (S) search in K to pi S, S to mu+ mu- (scalar portal) are discussed.