WWBN AVideo is an open source video platform. In versions 26.0 and prior, AVideo's EPG (Electronic Program Guide) feature parses XML from user-controlled URLs and renders programme titles directly into HTML without any sanitization or escaping. A user with upload permission can set a video's epg_link to a malicious XML file whose <title> elements contain JavaScript. This payload executes in the browser of any unauthenticated visitor to the public EPG page, enabling session hijacking and account takeover.

Affected: Packagist: wwbn/avideo

## Summary

AVideo's EPG (Electronic Program Guide) feature parses XML from user-controlled URLs and renders programme titles directly into HTML without any sanitization or escaping. A user with upload permission can set a video's `epg_link` to a malicious XML file whose `<title>` elements contain JavaScript. This payload executes in the browser of any unauthenticated visitor to the public EPG page, enabling session hijacking and account takeover.

## Details

The vulnerability spans three files in the data flow:

**1. Entry point — `objects/videoAddNew.json.php:117-119`**

The `epg_link` parameter is stored with only a URL format check:

```php if (empty($_POST['epg_link']) || isValidURL($_POST['epg_link'])) { $obj->setEpg_link($_POST['epg_link']); } ```

This requires `User::canUpload()` (line 10) — not admin, just basic upload permission.

**2. XML parsing — `objects/EpgParser.php:321`**

Programme titles are extracted as raw strings with no sanitization:

```php $this->epgdata[$grouper ?: 0] = [ 'title' => (string) $element->title, // ... ]; ```

**3. Sink — `plugin/PlayerSkins/epg.php:343-351`**

Programme titles are interpolated directly into HTML output without `htmlspecialchars()` or any escaping:

```php } else if ($width <= $minimumWidth1Dot) { $text = "<abbr title=\"{$program['title']}\">.</abbr>"; // attribute injection } else if ($width <= $minimumWidth) { $text = "<abbr title=\"{$program['title']}\"><small ..."; // attribute…