WWBN AVideo is an open source video platform. Versions prior to 29.0 contain a stored DOM Cross-Site Scripting vulnerability in the YPTSocket plugin. Any unauthenticated remote attacker can execute arbitrary JavaScript in the authenticated origin of every administrator currently viewing a page that renders the YPTSocket online-users debug panel. plugin/YPTSocket/getWebSocket.json.php issues a signed WebSocket token to any anonymous caller, and MessageSQLiteV2::onOpen at plugin/YPTSocket/MessageSQLiteV2.php lines 91 and 110 reads the attacker-controlled webSocketSelfURI and page_title query parameters from the WebSocket connection URL with no validation. Both values persist into the in-memory SQLite connections table and broadcast inside the users_id_online array sent to every connected client; on the client, plugin/YPTSocket/script.js::updateSocketUserCard interpolates the broadcast page_title into an HTML template literal that is passed to jQuery $.append(html), which parses attacker bytes into live DOM nodes including <img> with inline event handlers. Successful attackers can can read non-HttpOnly cookies and the CSRF token rendered into the admin dashboard, issue authenticated requests to any admin-only endpoint, exfiltrate the admin dashboard DOM, and chain into any admin-context mutation. When the victim is an AVideo administrator, the attacker turns a single anonymous WebSocket connection into full administrative takeover via the admin's own session. This issue has bee…

Affected: Packagist: WWBN/AVideo

# Unauthenticated Stored DOM XSS via `page_title` Broadcast in AVideo YPTSocket Plugin

## Summary

A stored DOM Cross-Site Scripting vulnerability (CWE-79) in the AVideo YPTSocket plugin lets any unauthenticated remote attacker execute arbitrary JavaScript in the authenticated origin of every administrator currently viewing a page that renders the YPTSocket online-users debug panel. `plugin/YPTSocket/getWebSocket.json.php` issues a signed WebSocket token to any anonymous caller, and `MessageSQLiteV2::onOpen` at `plugin/YPTSocket/MessageSQLiteV2.php` lines 91 and 110 reads the attacker-controlled `webSocketSelfURI` and `page_title` query parameters from the WebSocket connection URL with no validation. Both values persist into the in-memory SQLite `connections` table and broadcast inside the `users_id_online` array sent to every connected client; on the client, `plugin/YPTSocket/script.js::updateSocketUserCard` interpolates the broadcast `page_title` into an HTML template literal that is passed to jQuery `$.append(html)`, which parses attacker bytes into live DOM nodes including `<img>` with inline event handlers.

## Details

`plugin/YPTSocket/getWebSocket.json.php` issues a WebSocket token to any caller; the only gate is `AVideoPlugin::isEnabledByName("YPTSocket")`. The token-issuance helper `getEncryptedInfo()` at `plugin/YPTSocket/functions.php:21-24` writes `$_REQUEST['webSocketSelfURI']` directly into the per-token state without validation:

```php // plugin/YPTSocket/f…