Rar file extracts to multiple GB+ (like a zip bomb) but 'unrar' decompresses the correct 16.8MiB
I ran into the below file on Asus' web forums, it contains a 16.8MB .CAP file that unrars without issue with Arch's unrar package.
CROSSHAIR-VI-HERO-ASUS-7304.rar
I'm currently using Arch's default 3.32.1 release of file-roller.