{"id":"GHSA-944x-pm95-3jpr","revision":"50a5f0e4fc15499ebf2539186e0f1595","records":[{"revision":"50a5f0e4fc15499ebf2539186e0f1595","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-944x-pm95-3jpr","aliases":["BIT-ghost-2026-53948","CVE-2026-53948"],"title":"Ghost: File Upload Content-Type Spoofing","description":"### Impact\n\nInsufficient 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.\n\n### Vulnerable versions\n\nThis vulnerability is present in Ghost from v6.19.4 up to v6.21.0.\n\n### Patches\n\nv6.21.1 contains a fix for this issue.\n\n### How to update\n\nFor 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). \n\nIf your Ghost is a Ghost-CLI install see our documentation on [updating it to the latest version here](https://docs.ghost.org/update). \n\n### For more information\n\nIf you have any questions or comments about this advisory, email us at [security@ghost.org](mailto:security@ghost.org).","state":0,"publishedAt":"2026-08-04T21:05:39+00:00","modifiedAt":"2026-08-04T21:15:19.7873791+00:00","affected":[{"ecosystem":"npm","name":"ghost","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"6.19.4"},{"kind":"fixed","version":"6.21.1"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/TryGhost/Ghost/security/advisories/GHSA-944x-pm95-3jpr","https://nvd.nist.gov/vuln/detail/CVE-2026-53948","https://github.com/TryGhost/Ghost/pull/26751","https://github.com/TryGhost/Ghost/commit/d659e752d6636144d75b9aa94062cdbc88a16b21","https://github.com/TryGhost/Ghost","https://github.com/TryGhost/Ghost/releases/tag/v6.21.1"],"sourceUrl":"https://github.com/advisories/GHSA-944x-pm95-3jpr","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-944x-pm95-3jpr","identifiers":["GHSA-944x-pm95-3jpr","BIT-ghost-2026-53948","CVE-2026-53948"]},"retained":false,"historicalAffected":[]}],"coverage":[]}