2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/121730Distortions of CMB temperature and polarization maps caused by gravitational lensing, observable with high angular resolution and sensitivity, can be used to constrain the sterile neutrino mass, m_s, from CMB data alone. We forecast m_s>1.75 keV from Planck and m_s>4.97 keV from Inflation Probe at 95% CL, by using the CMB weak lensing extraction.to appear in Proceedings of Eleventh Marcel Grossmann Meeting on General Relativity (5 pages, 1 figure)Astrophysicstext