GitLab CE/EE, versions 8.18 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, are vulnerable to an SSRF vulnerability in webhooks.
GitLab EE, versions 8.3 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, is vulnerable to an insecure object reference vulnerability that allows a Guest user to set the weight of an issue they create.
GitLab EE, versions 11.4 before 11.4.8 and 11.5 before 11.5.1, is affected by an insecure direct object reference vulnerability that permits an unauthorized user to publish the draft merge request comments of another user.
GitLab CE/EE, versions 8.0 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, would log access tokens in the Workhorse logs, permitting administrators with access to the logs to see another user's token.
GitLab CE/EE, versions 8.6 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, are vulnerable to an access control issue that allows a Guest user to make changes to or delete their own comments on an issue, after the issue was made Confidential.
GitLab CE/EE, versions 8.8 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, are vulnerable to an authorization vulnerability that allows access to the web-UI as a user using a Personal Access Token of any scope.
GitLab CE/EE, versions 11.3 before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, are vulnerable to an XSS vulnerability in Markdown fields via unrecognized HTML tags.
GitLab CE 8.17 and later and EE 8.3 and later have a symlink time-of-check-to-time-of-use race condition that would allow unauthorized access to files in the GitLab Pages chroot environment. This is fixed in versions 11.5.1, 11.4.8, and 11.3.11.
GitLab CE/EE, versions 10.3 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, are vulnerable to an XSS vulnerability in Markdown fields via Mermaid.