Admidio is a free, open source user management system for websites of organizations and groups. In Admidio before version 4.0.4, there is an authenticated RCE via .phar file upload. A php web shell can be uploaded via the Documents & Files upload feature. Someone with upload permissions could rename the php shell with a .phar extension, visit the file, triggering the payload for a reverse/bind shell. This can be mitigated by excluding a .phar file extension to be uploaded (like you did with .php .phtml .php5 etc). The vulnerability is patched in version 4.0.4.
SQL Injection was discovered in Admidio before version 3.3.13. The main cookie parameter is concatenated into a SQL query without any input validation/sanitization, thus an attacker without logging in, can send a GET request with arbitrary SQL queries appended to the cookie parameter and execute SQL queries. The vulnerability impacts the confidentiality of the system. This has been patched in version 3.3.13.