The Easy Form Builder WordPress plugin before 3.4.0 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/fee8652d-cd50-4cb0-b94d-2d124f56af1a