In all versions of GitLab CE/EE since version 8.0, a DNS rebinding vulnerability exists in Fogbugz importer which may be used by attackers to exploit Server Side Request Forgery attacks.
https://gitlab.com/gitlab-org/gitlab/-/issues/214399
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39894.json