MonstaFTP v2.10.3 was discovered to contain a Server-Side Request Forgery (SSRF) via the function performFetchRequest at HTTPFetcher.php.
https://hackread.com/monsta-ftp-flaw-web-servers-open-server-takeover/
https://github.com/zer0yu/CVE_Request/blob/master/MonstaFTP/MonstaFTP_v2_10_3_SSRF.md