CVE-2026-53948
MEDIUM
MEDIUM
Priority: 0.01
BB Relevance:
51/100
Published: 2026-06-24
Modified: 2026-10-25
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
Scope Change
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
Low
UI:
Required
S:
Changed
C:
Low
I:
Low
A:
None
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. This vulnerability is fixed in 6.21.1.