OpenRepeater (ORP) before 2.2 allows unauthenticated command injection via shell metacharacters in the functions/ajax_system.php post_service parameter.
https://github.com/codexlynx/CVE-2019-25024
https://github.com/OpenRepeater/openrepeater/issues/66
https://github.com/MarkLee131/awesome-web-pocs/blob/main/CVE-2019-25024.md