Insufficient sanitization of the category EULA text field allows users with low-privilege permissions to inject markdown image syntax or raw HTML img tags. These tags can point to local files or remote URLs, which the mail auto-embed library resolves server-side and includes as email attachments. This behavior enables Server-Side Request Forgery (SSRF), a technique where an attacker induces the server to make requests to an unintended location, and the exfiltration of sensitive files such as `.env` credentials.