Abstract: A search for the exotic decay of SM Higgs boson with a 125 GeV mass to a pair of light scalars is being performed with b hadrons and τ leptons in the final state. Proton-proton collisions data recorded during Run 2 by the CMS detector at √s = 13 TeV is analyzed. A theory model proposing extension of SM scalar sector by 2 real scalar singlets is investigated. Machine learning techniques are used for event categorization.