NPM: Ghost: Member existence leak via magic link sign-in response

NPM: Ghost: Member existence leak via magic link sign-in response vulnerability discovered by ? in WordPress Npm ghost versions = 5.18.0, 6.21.1...

CVE-2026-53947

Ghost (Node.js CMS) contains a member existence leak via the magic link sign-in flow in versions 5.18.0–6.21.0, caused by differing responses from the members signin endpoints. An unauthenticated user could confirm whether an email is registered on a Ghost site. The issue is fixed in version 6.21...