An issue was discovered in GitLab Community Edition and Enterprise Edition 10.7.x before 10.7.6. The usage of 'url_for' contained a XSS issue due to it allowing arbitrary protocols as a parameter.
https://gitlab.com/gitlab-org/gitlab-ce/issues/45168
https://about.gitlab.com/2018/06/25/security-release-gitlab-11-dot-0-dot-1-released/