CVE-2026-53948 (GCVE-0-2026-53948)

Vulnerability from cvelistv5 – Published: 2026-06-24 18:06 – Updated: 2026-06-25 13:17
VLAI
Title
Ghost: File Upload Content-Type Spoofing
Summary
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.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-25 13:17 UTC
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
References
Impacted products
Vendor Product Version CPE status
TryGhost Ghost Affected: >= 6.19.4, < 6.21.1
guessed Create a notification for this product.
Show details on NVD website
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Nomenclature

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