This does not look like an insect pupa, though we are not certain what it actually is. Insect pupae tend to have visible wings, legs, multiple body segments, antennae, and other features of the adult insect detectable on the surface of it's "skin" (exoskeleton), which we do not see here. If you cut one in half, is the inside gooey/liquidy? If not, it's not a live insect. We recommend you work with a pest control professional if this is suspected to be a household pest, though usually sanitation measures are sufficient to eradicate infestations instead of having to resort to insecticide treatments.

Miri