GitLab Community Edition (CE) and Enterprise Edition (EE) before 8.17.8, 9.0.x before 9.0.13, 9.1.x before 9.1.10, 9.2.x before 9.2.10, 9.3.x before 9.3.10, and 9.4.x before 9.4.4 might allow remote attackers to execute arbitrary code via a crafted SSH URL in a project import.
GitLab Enterprise Edition (EE) before 8.17.7, 9.0.11, 9.1.8, 9.2.8, and 9.3.8 allows an authenticated user with the ability to create a project to use the mirroring feature to potentially read repositories belonging to other users.
GitLab before 8.14.9, 8.15.x before 8.15.6, and 8.16.x before 8.16.5 has XSS via a SCRIPT element in an issue attachment or avatar that is an SVG document.
Multiple versions of GitLab expose a dangerous method to any authenticated user that could lead to the deletion of all Issue and MergeRequest objects on a GitLab instance. For GitLab instances with publicly available projects this vulnerability could be exploited by an unauthenticated user. A fix was included in versions 8.14.3, 8.13.8, and 8.12.11, which were released on December 5th 2016 at 3:59 PST. The GitLab versions vulnerable to this are 8.13.0, 8.13.0-ee, 8.13.1, 8.13.1-ee, 8.13.2, 8.13.2-ee, 8.13.3, 8.13.3-ee, 8.13.4, 8.13.4-ee, 8.13.5, 8.13.5-ee, 8.13.6, 8.13.6-ee, 8.13.7, 8.14.0, 8.14.0-ee, 8.14.1, 8.14.2, and 8.14.2-ee.