Multiple SQL Injection vulnerabilities exist in amansuryawanshi Gym-Management-System-PHP 1.0 via the 'name', 'email', and 'comment' parameters in (1) submit_contact.php, the 'username' and 'pass_key' parameters in (2) secure_login.php, and the 'login_id', 'pwfield', and 'login_key' parameters in (3) change_s_pwd.php. An unauthenticated or authenticated attacker can exploit these issues to bypass authentication, execute arbitrary SQL commands, modify database records, delete data, or escalate privileges to administrator level.