/usr/share/man/man5/remotes.5.gz is in nullmailer 1:1.11-2.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man5/../man8/nullmailer-send.8.gz
/usr/share/man/man5/../man8/nullmailer-send.8.gz