Aug 6, Stinky smell emanated under the toenails is due to toenail infection either They also form cheese like white material underneath the toenail. My toenail smells like cheese and vomit - Yellowish substance that smells like cheese under my big toenails. It is not puss. My toenails are dull and my small toe . Jun 4, Do your nails have white stuff under the toenail? white stuff under toenail. Well don`t panic but it sounds like you have Onychomycosis.