They actually have both

A Komodo dragon’s killing power is intensified by a combination of secondary weapons: venom and bacteria. The sharp, serrated shape of a Komodo dragon’s tooth makes it easy for bits of rotten flesh to get caught in the reptile’s mouth, turning their saliva into a mini-habitat for harmful bacteria that can cause untreated bite wounds to become septic. Researchers have also documented a venom gland in the dragon’s lower jaw. This venom prevents their prey’s blood from clotting, which causes massive blood loss and induces shock. Even larger prey animals like water buffaloes may succumb to their wounds after escaping an initial attack—although it may take days for that to happen.

This is a newish discovery due to the protections of the dragon and the location of the venom sack, at least from what I can remember.