Contest Gallery < 34.0.3 - Author+ Arbitrary File Upload via Ecommerce Sale File Replacement

The Contest Gallery WordPress plugin before 34.0.3 does not sanitise the name of files uploaded through its e-commerce sale file-replacement feature, allowing authenticated users with Author-level access and above to write files with an arbitrary name and extension to a web-accessible directory and, by overwriting the directory's protection file through the same flow, achieve Remote Code Execution.