The Social Slider Feed WordPress plugin before 2.2.9 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).
The Social Slider Widget WordPress plugin before 1.8.5 allowed Authenticated Reflected XSS in the plugin settings page as the ‘token_error’ parameter can be controlled by users and it is directly echoed without being sanitized