Recent results on searches for rare decays of the Higgs boson, obtained using 35.9 fb$^{-1}$ of proton-proton collision data collected at ${\sqrt{s} = 13\,\mathrm{TeV}}$ with the CMS detector, are presented. This report includes searches for the Higgs boson decaying into invisible particles, muon pairs, ${\mathrm{J}/\psi\,\gamma}$ and ${\mathrm{Z}\gamma}$ final states. No significant deviations from the standard model predictions have been observed and upper limits are placed on the corresponding decay branching fractions.