The Simple File List WordPress plugin before 6.0.10 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/13621b13-8d31-4214-a665-cb15981f3ec1