The 5 sigma mismatch between CMB and local distance ladder measurements of Hubble parameter is one of the greatest challenge to our well known Lambda CDM model of cosmology. I will discuss that one needs beyond standard model particle physics to appear before and close to CMB epoch if the anomaly persists. I will also present a scenario where secret BSM neutrino interaction can play a crucial role to relax the mismatch and also point to predictions of such new physics in cosmological observables.