CVE-2026-70596

### Impact An input validation issue allowed any staff user to create a post with content that could be used to hijack another staff user's Ghost Admin session resulting in privilege escalation. ### Vulnerable versions This vulnerability is present in Ghost from v4.9.0 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 Versa for disclosing this vulnerability responsibly. ### For more information If you have any questions or comments about this advisory, email Ghost at [security@ghost.org](mailto:security@ghost.org).

Ghost is a Node.js content management system. From 4.9.0 until 6.54.1, an input validation issue allowed any staff user to create a post with content in feature_image_caption that could be used to hijack another staff user's Ghost Admin session, resulting in privilege escalation. This issue is fixed in 6.54.1.