GitHub Advisoryadvisory · npm

GHSA-wvp2-4qqp-4h3r Ghost: Private IP filtering bypass to make server-side requests to internal services

MEDIUM Published 2026-08-04 Modified 2026-08-04 Official page ↗
Aliases
CVE-2026-53944
Ecosystem
npm
Packages
ghost
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Weaknesses
CWE-184, CWE-918
Reviewed
2026-08-04

Affected packages

• npm ghost: >= 6.0.9, < 6.21.1 → fixed in 6.21.1

Description

Impact When making an external request, it is possible to bypass the IP filter that ensures the request isn't going to an internal service using an IPv6 literal which maps to a private IPv4 address. Vulnerable versions This vulnerability is present in Ghost from v6.0.9 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. References Ghost thanks l3tchupkt for disclosing this vulnerability responsibly. For more information If you have any questions or comments about this advisory, email us at [email protected].

Related

Alias · CVE (1)

  • CVE-2026-53944 Ghost is a Node.js content management system. vulnerability

Weakness · CWE (2)

  • CWE-184 Incomplete List of Disallowed Inputs weakness
  • CWE-918 Server-Side Request Forgery weakness

References