Stored XSS via html file upload in convos

Convos is an open source multi-user chat that runs in a web browser. You can't use SVG extension in Convos' chat window, but you can upload a file with an .html extension. By uploading an SVG file with an html extension the upload filter can be bypassed. This causes Stored XSS. Also, after uploading a file the XSS attack is triggered upon a user viewing the file. Through this vulnerability, an attacker is capable to execute malicious scripts. Users are advised to update as soon as possible.