Passive optical limiting, that is the passive restriction of light above a threshold intensity, enables the protection of sensitive device architectures without the need for any external activation. This prospect has thus drawn substantial attention in physics and design, however it has yet to be fully realized by current optical materials. Recently there have been advances in meta materials and nanophotonics that can expand the possible routes of optical limiting, however, many of these materials suffer from high optical losses as they are extended into the mid-infrared. In this work we experimentally demonstrate an ultrafast passive optical limiter based off the nonlinear response of the epsilon-near-zero material CdO. Thus, we demonstrate a wavelength tunable 30% reduction in transmitted light within the ENZ region and provide a mechanistic explanation of the physical process that govern passive optical limiting. Furthermore, by comparing interband and intraband excitations, we demonstrate markedly different limiter recovery times, providing a route toward engineering the temporal response of passive optical limiters.