The Mobile Contact Bar WordPress plugin before 3.0.5 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).
https://wpscan.com/vulnerability/5492f1b2-481b-472a-82d3-949f85c8dc70/