CVE-2026-90543WWBN AVideo at commit c3edcc274c389816d434acadac07ee78eaf330c1 and earlier, with the Live plugin enabled, contains a missing authentication vulnerability in plugin/Live/socketMessageLiveOwner.json.php. The script reads the `key` and `msg` parameters from $_REQUEST, resolves the stream owner via LiveTransmition::keyExists, and verifies that the stream owner (not the caller) is an administrator; it performs no User::isLogged() check and enforces no CSRF token. As a result, an unauthenticated remote attacker who knows an administrator's Live stream key can call sendSocketSuccessMessageToUsers_id and deliver arbitrary in-app/socket notification messages to that administrator. The issue was unpatched at the time of publication.