An article published by iDrop News reports than an Ohio man has suffered injury from his iPhone XS Max catching fire whilst in the back pocket of his pants. Apparently, the device was completely destroyed in the incident, and the blaze also damaged his pants and burned the skin of his buttocks. It seems the individual is now considering legal action against Apple.
https://www.notebookcheck.net/Man-claims-iPhone-XS-Max-exploded-in-his-pants-pocket.388016.0.html