AVideo has Authenticated Server-Side Request Forgery via downloadURL in aVideoEncoder.json.php

WWBN AVideo is an open source video platform. Prior to version 22.0, the `aVideoEncoder.json.php` API endpoint accepts a `downloadURL` parameter and fetches the referenced resource server-side without proper validation or an allow-list. This allows authenticated users to trigger server-side requests to arbitrary URLs (including internal network endpoints). An authenticated attacker can leverage SSRF to interact with internal services and retrieve sensitive data (e.g., internal APIs, metadata services), potentially leading to further compromise depending on the deployment environment. This issue has been fixed in AVideo version 22.0.