Open Source Point of Sale (opensourcepos) is a web based point of sale application written in PHP using CodeIgniter framework. Prior to version 3.4.2, an Insecure Direct Object Reference (IDOR) vulnerability allows an authenticated low-privileged user to access the password change functionality of other users, including administrators, by manipulating the `employee_id` parameter. The application does not verify object ownership or enforce authorization checks. Version 3.4.2 adds object-level authorization checks to validate that the current user owns the employee_id being accessed.