Provide references for CVE-2020-23839.
Where can I find more information about CVE-2020-23839?
References are available at: https://github.com/GetSimpleCMS/GetSimpleCMS/issues/1330, http://packetstormsecurity.com/files/162016/GetSimple-CMS-3.3.16-Cross-Site-Scripting-Shell-Upload.html, https://www.exploit-db.com/exploits/49726, https://github.com/boku7/CVE-2020-23839.