A cross-site request forgery (CSRF) vulnerability in Jenkins GitLab Authentication Plugin 1.17.1 and earlier allows attackers to trick users into logging in to the attacker's account.

Jenkins GitLab Authentication Plugin 1.13 and earlier stores the GitLab client secret unencrypted in the global config.xml file on the Jenkins controller where it can be viewed by users with access to the Jenkins controller file system.

Jenkins GitLab Authentication Plugin 1.13 and earlier records the HTTP Referer header as part of the URL query parameters when the authentication process starts, allowing attackers with access to Jenkins to craft a URL that will redirect users to an attacker-specified URL after logging in.

Jenkins Gitlab Authentication Plugin 1.5 and earlier does not perform group authorization checks properly, resulting in a privilege escalation vulnerability.