static-web-server vulnerable to stored Cross-site Scripting in directory listings via file names

Summary

If directory listings are enabled for a directory that an untrusted user has upload privileges for, a malicious file name like <img src=x onerror=alert(1)>.txt will allow JavaScript code execution in the context of the web server’s domain.

Details

SWS generally does not perform escaping of HTML entities on any values inserted in the directory listing. At the very least file_name and current_path could contain malicious data however. file_uri could also be malicious but the relevant scenarios seem to be all caught by hyper.

Impact

For any web server that allow users to upload files or create directories under a name of their choosing this becomes a stored XSS vulnerability.