An issue was discovered in GitLab Community and Enterprise Edition before 11.5.8, 11.6.x before 11.6.6, and 11.7.x before 11.7.1. It has Incorrect Access Control (issue 3 of 3). When a project with visibility more permissive than the target group is imported, it will retain its prior visibility.
Source: NIST
CVE-2019-6791