An information disclosure issue was discovered in GitLab CE/EE 8.14 and later, by using the move issue feature which could result in disclosure of the newly created issue ID.
An issue was discovered in GitLab Enterprise Edition (EE) 8.9.0 through 12.6.1. Using the project import feature, it was possible for someone to obtain issues from private projects.
In GitLab EE 10.5 through 12.5.3, 12.4.5, and 12.3.8, when transferring a public project to a private group, private code would be disclosed via the Group Search API provided by the Elasticsearch integration.
GitLab EE 8.14 through 12.5, 12.4.3, and 12.3.6 has Incorrect Access Control. After a project changed to private, previously forked repositories were still able to get information about the private project through the API.