The Login Screen Manager WordPress plugin through 3.5.2 does not sanitize 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/ad895200-a03a-4e92-b256-d6991547d38a