An unrestricted file upload vulnerability in the Add New Assets function of Strapi 4.1.12 allows attackers to conduct XSS attacks via a crafted PDF file. NOTE: the project documentation suggests that a user with the Media Library "Create (upload)" permission is supposed to be able to upload PDF files containing JavaScript, and that all files in a public assets folder are accessible to the outside world (unless the filename begins with a dot character). The administrator can choose to allow only image, video, and audio files (i.e., not PDF) if desired.
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.