Ghost: Server-Side Request Forgery Mitigation Issue

### Impact 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. A successful attack would not result in any response data being returned. ### Vulnerable versions This vulnerability is present in Ghost from v6.26.0 up to v6.54.0. ### Patches v6.54.1 contains a fix for this issue. ### How to update For self-hosters using Docker, find [Docker's official Ghost image here](https://hub.docker.com/_/ghost). Updating a Docker-based Ghost instance [is documented here](https://docs.ghost.org/install/docker#updating-ghost). If your Ghost is a Ghost-CLI install see our documentation on [updating it to the latest version here](https://docs.ghost.org/update). ### References Ghost thanks Hwang Seyeon for disclosing this vulnerability responsibly. ### For more information If you have any questions or comments about this advisory, email Ghost at [[email protected]](mailto:[email protected]).

Source published

5 Aug 2026 14:37:14 UTC

Source modified

17 Aug 2026 08:10:51 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N

Publisher rating · MODERATE