CVE-2026-53948: Ghost is a Node.js content management system. From 6.19.4 until 6.21.1, insufficient validation of the client-supplied C…
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. This vulnerability is fixed in 6.21.1.
- Published by source
- 2026-06-24
- First seen by Reality Radar
- 2026-10-26
- Last verified
- 2026-10-26
What the official notice says
Risk: CVSS 5.4
Is this affecting you?
Add what you own or use and Reality Radar will tell you when official changes match it — with evidence and next steps.
Sources
- NIST National Vulnerability Database Tier A · official published 2026-06-24
Evidence ledger
Every piece of evidence we store is appended to a public hash chain, so later edits are detectable. Anyone can re-verify it.
| Entry | Kind | Observed | Evidence hash | Entry hash |
|---|---|---|---|---|
| #1743 | new | 2026-10-26 | cdef03af2578…ef57b8 | b08696e775e2…3b4d3c |
Chain head: #1771 9d8a5938d304…171807