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 unfilteredhtml capability is disallowed (for example in multisite setup).
The Easy Form Builder by WhiteStudio WordPress plugin before 4.2.0 does not validate a submitted value against the stored configuration for some of its form types, allowing unauthenticated users to store arbitrary content which is then rendered unescaped in an admin page, leading to Stored XSS.
The Easy Form Builder by WhiteStudio WordPress plugin before 4.2.0 does not validate a submitted value against the stored configuration for some of its form types, allowing unauthenticated users to create WordPress accounts on a site whose owner has disabled registration.