{"schemaVersion":3,"id":"CVE-2026-53948","aliases":["GHSA-944x-pm95-3jpr","BIT-ghost-2026-53948"],"status":"published","duplicateOf":null,"title":null,"description":"Ghost is a Node.js content management system. From 6.19.4 until 6.21.1, insufficient validation of the client-supplied Content-Type on Ghost's Admin API file upload endpoint allowed uploaded files to be served from the site with an attacker-chosen content type on S3/GCS storage backends. On installations that serve uploaded files from the same origin as the site, this could have been used to facilitate stored cross-site scripting against site visitors or staff. 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