Exotic charmonium spectroscopy with CMS

The latest results of CMS in the area of exotic quarkonium decays will be presented: observation of a peaking structure in $J/\psi\Phi$ mass spectrum in the decay $B^\pm \rightarrow J/\psi \Phi K^\pm$, search for new bottomonium states in $\Upsilon(1\mathrm{S})\pi^+\pi^-$ mass spectrum, measurement of prompt $J/\psi$ pair production.