Quick Playground <= 1.3.1 - Missing Authorization to Unauthenticated Arbitrary File Upload

The Quick Playground plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 1.3.1. This is due to insufficient authorization checks on REST API endpoints that expose a sync code and allow arbitrary file uploads. This makes it possible for unauthenticated attackers to retrieve the sync code, upload PHP files with path traversal, and achieve remote code execution on the server.