Ghost is a Node.js content management system. From 6.0.9 until 6.65.0, a validation issue allowed some functionality, such as Webmentions, to be abused by an unauthenticated user to make limited HTTP requests to hosts in the Ghost server's internal network on some network configurations. A successful attack would not result in any response data being returned. This issue is fixed in version 6.65.0.
Analyzing vulnerability vectors…