The Newsletter, SMTP, Email marketing and Subscribe forms by Sendinblue WordPress plugin before 3.1.61 does not sanitise and escape a parameter before outputting it back in the admin dashboard when the WPML plugin is also active and configured, leading to a Reflected Cross-Site Scripting which could be used against high privilege users such as admin
https://wpscan.com/vulnerability/b0e7665a-c8c3-4132-b8d7-8677a90118df