GoCD is a continuous deliver server. GoCD versions 16.7.0 through 24.4.0 (inclusive) can allow GoCD admins to abuse a hidden/unused configuration repository (pipelines as code) feature to allow XML External Entity (XXE) injection on the GoCD Server which will be executed when GoCD periodically scans configuration repositories for pipeline updates, or is triggered by an administrator or config repo admin. In practice the impact of this vulnerability is limited, in most cases without combining with another vulnerability, as only GoCD (super) admins have the ability to abuse this vulnerability.

Typically a malicious GoCD admin can cause much larger damage than that they can do with XXE injection. The issue is fixed in GoCD 24.5.0. As a workaround, prevent external access from the GoCD server to arbitrary locations using some kind of environment egress control.