The Download Manager plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'icon' Shortcode Attribute in all versions up to, and including, 3.3.66 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. wp_kses_post() does not neutralize the payload because it operates on post content at save time and does not process shortcode attribute values that are emitted unescaped at render time.