Force carrying particles in general don&#x27;t have mass. Except that some of them seem to do, which was rather puzzling for some time, but was solved using the Higgs mechanism.<p>I can&#x27;t think of an obvious reason the Higgs mechanism wouldn&#x27;t work for gravitons, but I could be mistaken, it&#x27;s not exactly the most intuitive area of physics.<p>Also, keep in mind that the strong force transmits the force between colour charges while also having a colour charge itself, so it isn&#x27;t entirely inconceivable for the force transmitting the attraction between masses to have a mass.<p>No clue if a massive graviton would allow for black holes, but it&#x27;s not entirely sure what black holes even are (especially quantum mechanically). At the very least it&#x27;s presumably possible for <i>some</i> particles to escape it (e.g. as Hawking radiation).