The Google CSE WordPress plugin through 1.0.7 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/adc6ea6d-29d8-4ad0-b0db-2540e8b3f9a9/