WordPress Subscribe Sidebar plugin <= 1.3.1 - Authenticated Reflected Cross-Site Scripting (XSS) vulnerability

Authenticated Reflected Cross-Site Scripting XSS vulnerability found by ZeroAptitude in WordPress Subscribe Sidebar plugin versions = 1.3.1. Solution 2020-12-28 - we were unable to find a patched version of this plugin. Notice from WordPress.org: "This plugin has been closed as of June 23, 2020 a...