/usr/lib/mon/mon.d/softraid.monitor is in mon-contrib 1.0+dfsg-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/mon/mon.d/../../mon-contrib/mon.d/softraid.monitor
/usr/lib/mon/mon.d/../../mon-contrib/mon.d/softraid.monitor