Ghost is an app for new-media creators with tools to build a website, publish content, send newsletters, and offer paid subscriptions to members. Prior to version 5.46.1, due to a lack of validation when filtering on the public API endpoints, it is possible to reveal private fields via a brute force attack.
Ghost(Pro) has already been patched. Maintainers can find no evidence that the issue was exploited on Ghost(Pro) prior to the patch being added. Self-hosters are impacted if running Ghost a version below v5.46.1. v5.46.1 contains a fix for this issue. As a workaround, add a block for requests to `/ghost/api/content/*` where the `filter` query parameter contains `password` or `email`.