ApiAdmin v5.0 and before is vulnerable to Directory Traversal. The admin file-upload endpoint POST /admin/Index/upload in ApiAdmin takes the uploaded file's extension verbatim there is no whitelist, blacklist or content check and move_uploaded_file() drops the file into the web-accessible directory public/upload/Ymd/. Any logged-in admin user can upload a .php file and reach it directly over HTTP, achieving remote code execution on the server.
Analyzing vulnerability vectors…