The WP STAGING WordPress plugin before 2.9.18 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/91bbdeb0-f2df-4500-b856-af0ff68fbb12