Copyparty is a portable file server. In versions 1.18.6 and below, when accessing the recent uploads page at `/?ru`, users can filter the results using an input field at the top. This field appends a filter parameter to the URL, which reflects its value directly into a `<script>` block without proper escaping, allowing for reflected Cross-Site Scripting (XSS) and can be exploited against both authenticated and unauthenticated users. This is fixed in version 1.18.7.
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.