The most common "cracked PDF" is not a PDF at all. It’s a .exe file, an archive with a password, or a file that asks you to disable your antivirus. These are classic vectors for:
L'atelier + B1 - Cahier numérique - eboutique.didierfle.com l 39atelier b1 cahier d 39activites pdf cracked
For specific PDF resources or activities: The most common "cracked PDF" is not a PDF at all