Text files with the word "Encrypted" in the text are seen as password protected pdf files instead

When I’m trying to upload a text file, if the word “Encrypted” (case matters) is somewhere in the text the upload will fail with the error “password pdf file is not supported” or something like that. It wasn’t a pdf file at all. It was a text file.

I tracked this bug to the presence of the word “Encrypted” somewhere in the text inside the file. the word “encrypted” doesn’t trigger this. I haven’t tried any other combinations of case variations.