Webmin 1.973 is affected by Cross Site Request Forgery (CSRF) to create a privileged user through Webmin's add users feature, and then get a reverse shell through Webmin's running process feature.
https://github.com/webmin/webmin
https://github.com/electronicbots/CVE-2021-31762
https://github.com/Mesh3l911/CVE-2021-31762
http://packetstormsecurity.com/files/163492/Webmin-1.973-Cross-Site-Request-Forgery.html