/usr/lib/x86_64-linux-gnu/libmagic.so is in libmagic-dev 1:5.14-2ubuntu3.4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libmagic.so.1.0.0
/usr/lib/x86_64-linux-gnu/libmagic.so.1.0.0