The vulnerability stems from improper wildcard handling in Laravel's validation component (illuminate/validation). While the laravel-crud-wizard-free package itself didn't contain vulnerable code, it became vulnerable by depending on unpatched Laravel versions (<11.44.1). The key vulnerable functions are in Laravel's Validator class: parseData() (improper array key sanitization) and replaceDotInParameters() (flawed wildcard normalization). The package's fix involved implementing a custom ValidationServiceProvider to override these methods with proper placeholder handling.