WordPress Portrait-Archiv.com Photostore plugin <= 3.1 - Unauthenticated Reflected Cross-Site Scripting (XSS) vulnerability

Unauthenticated Reflected Cross-Site Scripting XSS vulnerability found by Ricardo Sanchez in WordPress Portrait-Archiv.com Photostore plugin versions = 3.1 Solution 8 Sep 2019 - we were unable to find a patched version of this plugin...