The plugin 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)
1. Add a new item in the plugin settings
2. Enter the payload `javascript:alert(/XSS/);` in the "Link" field
3. Go to the homepage, and click on the generated link to trigger the XSS