The Hostel WordPress plugin before 1.1.5.2 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/b604afc8-61d0-4e98-8950-f3d29f9e9ee1