CVE-2026-53948

Ghost: File Upload Content-Type Spoofing

Published Jun 24, 2026 CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-944x-pm95-3jpr Ghost: File Upload Content-Type Spoofing
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Ghost
Ghost ghost
Vendors & Products Ghost
Ghost ghost
Type Values Removed Values Added
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.
Title Ghost: File Upload Content-Type Spoofing
Weaknesses CWE-434
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 25, 2026, 1:17 PM
Reserved
Jun 11, 2026, 3:50 PM
Status
Deferred
Published
Jun 24, 2026, 7:17 PM
Modified
Oct 25, 2026, 10:10 PM