/usr/share/doc/libbson-dbg/changelog.Debian.gz is in libbson-dbg 1.3.1-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libbson-dbg/../libbson-1.0-0/changelog.Debian.gz
/usr/share/doc/libbson-dbg/../libbson-1.0-0/changelog.Debian.gz