There's a difference between exploiting bugs that haven't even been found and spreading malware through a method that's known by pretty much everyone and is still used to spread malware today.
It's also theoretically possible that your system is already infected by some Advanced Persistent Threats but does that happen that often, No, and have people been infected by running random pdfs they found online, Yes.
I pirated this meme in the highest quality I could but lemmy compresses the image to 60-70% of its original quality, that's why it's so blurry ๐