CVE-2020-26286
HedgeDoc is a collaborative platform for writing and sharing markdown. In HedgeDoc before version 1.7.1 an unauthenticated attacker can upload arbitrary files to the upload storage backend including HTML, JS and PHP files. The problem is patched in HedgeDoc 1.7.1. You should however verify that your uploaded file storage only contains files that are allowed, as uploaded files might still be served. As workaround itโs possible to block the `/uploadimage` endpoint on your instance using your reverse proxy. And/or restrict MIME-types and file names served from your upload file storage.
Source: CVE-2020-26286