rcube_utils.php in Roundcube before 1.1.8 and 1.2.x before 1.2.4 is susceptible to a cross-site scripting vulnerability via a crafted Cascading Style Sheets (CSS) token sequence within an SVG element.
https://roundcube.net/news/2017/03/10/updates-1.2.4-and-1.1.8-released
https://github.com/roundcube/roundcubemail/wiki/Changelog#release-124
https://github.com/roundcube/roundcubemail/releases/tag/1.2.4
https://github.com/roundcube/roundcubemail/releases/tag/1.1.8
https://github.com/roundcube/roundcubemail/commit/fa2824fdcd44af3f970b2797feb47652482c8305
https://github.com/roundcube/roundcubemail/commit/cbd35626f7db7855f3b5e2db00d28ecc1554e9f4