CVE-2019-15583
An information disclosure exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE). When an issue was moved to a public project from a private one, the associated private labels and the private project namespace would be disclosed through the GitLab API.
Source: CVE-2019-15583