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.
replyI 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.
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.
replyMaybe the PDFs were malware?
replySorry 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.
replyI'm really trying to remember the context, I wish I'd written it down somewhere. But now that I'm thinking of it, I'm almost certain it wasn't PDFs, but JSON files that I'd written. For some reason it would allow me to open them in some applications, but in others I'd get a warning and the file would be trashed.
replyThe Docker thing happened as described in my linked post. It happened with something else too, but again I can't remember. I wasn't planning on doing a post mortem so I guess I let the details slip!
In any case, I do like most of the OS' ways of doing things, including security. But it can be overzealous.
P.S. I'm not crazy! I'm not crazy!!!