Now one year later still cannot find the solution:
I disable the ftp service in CWP pro dashboard:
Pure-FTPd service is disabled.
after cron.daily the ftp server is running again.
No other services are starting Pure-FTPd. All Services monitor are disabled(from dashboard), Monit also not installed
No cronjobs or other services with Pure-FTPd are enabled or starting.
The only cronjob I suspect is coming from here from:
/etc/cron.daily/cpw
But I cannot check because of Ioncube encode.
content of /etc/cron.daily/cpw
/usr/local/cwp/php71/bin/php -d max_execution_time=1000000 -q /usr/local/cwpsrv/htdocs/resources/admin/include/cron.php
/usr/local/cwp/php71/bin/php -d max_execution_time=1000000 -q /usr/local/cwpsrv/htdocs/resources/admin/include/cron_backup.php
Maybe CWP admins can help clear this? Thanks