/usr/share/man/man8/pure-ftpd-mysql.8.gz is in pure-ftpd-mysql 1.0.46-1build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man8/pure-ftpd.8.gz
/usr/share/man/man8/pure-ftpd.8.gz