Admidio is an open-source user management solution. Versions 5.0.6 and below are vulnerable to arbitrary SQL Injection through the MyList configuration feature. The MyList configuration feature lets authenticated users define custom list column layouts, storing user-supplied column names, sort directions, and filter conditions in the adm_list_columns table via prepared statements. However, these stored values are later read back and interpolated directly into dynamically constructed SQL queries without sanitization or parameterization, creating a classic second-order SQL injection vulnerability (safe write, unsafe read). An attacker can exploit this to inject arbitrary SQL, potentially reading, modifying, or deleting any data in the database and achieving full database compromise. This issue has been fixed in version 5.0.7.