I love when my Mac declares random PDFs malware and deletes them when I try to open them.
On two occasions I've been completely dumbstruck when the software I was using was deleted out from under me. I'm not a fan of the overuse of "gaslight", but it sure felt like that when I had to restart Docker and the OS was like "what do you mean, Docker? You've never had Docker installed! What are you talking about? Are you feeling ok?"
Just as a contrapoint to the other commenters, I've had Mac do this on PDFs that I myself scanned many years ago. Pretty sure they were not malware.
I suspect what triggered it was the fact that the files had journeyed through many filesystems in their time - HFS, ext4, NTFS, APFS - and they probably picked up some unholy combination of impossible attributes.
I thought it was pretty egregious to have Apple helpfully try to delete important PDFs that I've been lugging around for years.
Sorry to say but your PDFs were malware. In 20+ years I’ve never seen this on my Macs nor the literal thousands I’ve managed with various MDMs.
Maybe the PDFs were malware?
In ten years of using Macs, I have never encountered this behaviour. I've never heard this from anyone else either. Is this new in Tahoe? I haven't upgraded yet, but your link seems to be from before Tahoe was released.