Ask HN: What if I open on a malicious PDF AirDropped to my iPhone by a stranger?

The title says it all. I made a mistake. I opened my iPhone to receive AirDrop photos from a stranger. I later found a PDF in Files and tried to open (after disconnecting from the internet), but Files crashed and the file disappeared. I was on 18.4. I have since factory reset. Do you think it's possible that there's a PDF exploit I've been victim to?