GitLab EE 3.0 through 12.8.1 allows SSRF. An internal investigation revealed that a particular deprecated service was creating a server side request forgery risk.
https://about.gitlab.com/releases/2020/03/04/gitlab-12-dot-8-dot-2-released/index.html
https://about.gitlab.com/releases/2020/03/04/gitlab-12-dot-8-dot-2-released/