Netsparker detected a code execution via file upload. Netsparker successfully uploaded a file and when requesting the uploaded file, code is executed in the context of the web server.
The web server can be compromised by uploading and executing a web-shell which can run commands, browse system files, browse local resources, attack other servers, and exploit the local vulnerabilities, and so forth.
Never accept a filename and its extension directly without having a white-list filter.
Uploaded directory should not have any "execute" permission.