CVE-2026-34396: AVideo has Stored XSS via Unescaped Plugin Configuration Values in Admin Panel

The AVideo admin panel renders plugin configuration values in HTML forms without applying htmlspecialchars() or any other output encoding. The jsonToFormElements() function in admin/functions.php directly interpolates user-controlled values into textarea contents, option elements, and input attributes. An attacker who can set a plugin configuration value (either as a compromised admin or by chaining with CSRF on admin/save.json.php) can inject arbitrary JavaScript that executes whenever any administrator visits the plugin configuration page.

This vulnerability chains with AVI-046 (CSRF on save.json.php) to enable a full cross-origin stored XSS attack against the admin panel without requiring any prior authentication.