xbtitFM 4.1.18 Insecure File Upload in file_hosting Feature

xbtitFM 4.1.18 contains an insecure file upload vulnerability that allows authenticated attackers with administrative privileges to upload and execute arbitrary PHP code through the file_hosting feature. Attackers can bypass file type restrictions by modifying the Content-Type header to image/gif, adding GIF89a magic bytes, and using alternate PHP tags to upload web shells that execute system commands.