GHSA-944x-pm95-3jpr

Source

https://github.com/advisories/GHSA-944x-pm95-3jpr

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-944x-pm95-3jpr/GHSA-944x-pm95-3jpr.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-944x-pm95-3jpr

Aliases

Published

2026-08-04T21:05:39Z

Modified

2026-08-04T21:15:19.787379123Z

Severity

5.4 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N CVSS Calculator

Summary

Ghost: File Upload Content-Type Spoofing

Details

Impact

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.

Vulnerable versions

This vulnerability is present in Ghost from v6.19.4 up to v6.21.0.

Patches

v6.21.1 contains a fix for this issue.

How to update

For self-hosters using Docker, find Docker's official Ghost image here. Updating a Docker-based Ghost instance is documented here.

If your Ghost is a Ghost-CLI install see our documentation on updating it to the latest version here.

For more information

If you have any questions or comments about this advisory, email us at security@ghost.org.

Database specific

{
    "nvd_published_at": "2026-06-24T19:17:12Z",
    "cwe_ids": [
        "CWE-434"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-04T21:05:39Z"
}

References

Affected packages

npm / ghost

Package

Name: ghost; View open source insights on deps.dev
Purl: pkg:npm/ghost

Affected ranges

Type: SEMVER
Events: Introduced

6.19.4

Fixed

6.21.1

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-944x-pm95-3jpr/GHSA-944x-pm95-3jpr.json"