We summarize the latest cross-section measurements of vector boson scattering (VBS) production of two vector bosons in association with two jets. The analyses are based on the LHC proton-proton collisions at a center-of-mass energy of 13 TeV recorded with the CMS detector. VBS processes are powerful tools to shed light on the mechanism underlying the spontaneous breaking of the electroweak symmetry. Indeed, the unitarization of their cross sections is strictly related to the Higgs boson; any possible deviation from standard model predictions could lead to an enhancement of their cross sections, which could reveal the nature of what lies beyond the standard model.