/usr/share/doc/libcfitsio-bin/changelog.Debian.gz is in libcfitsio-bin 3.430-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libcfitsio-bin/../libcfitsio5/changelog.Debian.gz
/usr/share/doc/libcfitsio-bin/../libcfitsio5/changelog.Debian.gz