Potential DoS was identified in gitlab-shell in GitLab CE/EE version 12.6.0 or above, which allows an attacker to spike the server resource utilization via gitlab-shell command.
https://hackerone.com/reports/953444
https://gitlab.com/gitlab-org/gitlab/-/issues/238988
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-22177.json