以下是官方给出解释:
链接:https://docs.gitlab.com/ee/security/webhooks.html
If you have non-GitLab web services running on your GitLab server or within its local network, these may be vulnerable to exploitation via Webhooks.
With Webhooks, you and your project maintainers and owners can set up URLs to be triggered when specific things happen to projects. Normally, these requests are sent to external web services specifically set up for this purpose, that process the request and its attached data in some appropriate way.