CSRF exists in Webmin 1.850. By sending a GET request to at/create_job.cgi containing dir=/&cmd= in the URI, an attacker to execute arbitrary commands.
https://github.com/webmin/webmin/commit/0c58892732ee7610a7abba5507614366d382c9c9
https://euvd.enisa.europa.eu/vulnerability/EUVD-2017-7096
https://blogs.securiteam.com/index.php/archives/3430