CVE-2026-59817: Ghost Paid Gift Memberships Obtainable At Vulnerability

MODERATE
Advisory Identifier: GHSA-xm43-3m56-w3wf
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CVSS 5.3
CWE-639 CWE-472
Published
Advisory Summary

CVE-2026-59817 is a MODERATE (CVSS 5.3) paid gift memberships obtainable at vulnerability (CWE-639: Authorization Bypass Through User-Controlled Key) affecting Ghost libraries in the npm ecosystem. The issue involves paid gift memberships obtainable at minimal cost via the donations feature. Remediation is available by upgrading affected packages to version 6.44.0.

CVE-2026-59817 at a Glance

CVE Identifier CVE-2026-59817
GHSA Identifier GHSA-xm43-3m56-w3wf
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-639: Authorization Bypass Through User-Controlled Key
Affected Product Ghost
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-59817

To remediate this vulnerability, upgrade all affected Ghost dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

ghost fixed: 6.44.0 
npm install ghost@6.44.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls ghost

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-59817, inspect your project dependencies using npm:

npm ls ghost

Analyze the terminal output to locate any version of Ghost in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 6.44.0), your application is affected.

Note: The npm ls ghost command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-639: Authorization Bypass Through User-Controlled Key, where the system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. In Ghost, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact A vulnerability in Ghost's public donation checkout flow allowed an unauthenticated attacker to obtain full paid gift memberships for a minimal payment. No customer or member data was exposed, and the issue could not be used to steal money from a site or its members. ### Vulnerable versions This vulnerability is present in Ghost from [v6.27.0](https://github.com/TryGhost/Ghost/releases/tag/v6.27.0) up to [v6.43.1](https://github.com/TryGhost/Ghost/releases/tag/v6.43.1). ### Patches [v6.44.0](https://github.com/TryGhost/Ghost/releases/tag/v6.44.0) contains a fix for this issue. ### How to update For self-hosters using Docker, find [Docker’s official Ghost image on Docker Hub](https://hub.docker.com/_/ghost) and follow the documentation on [updating a Docker-based Ghost instance](https://docs.ghost.org/install/docker#updating-ghost). For self-hosters using Ghost-CLI, see the documentation for [updating Ghost to the latest version](https://docs.ghost.org/update). ### Workarounds If upgrading immediately is not possible, you can remove the vulnerable checkout path by disabling the donations feature in Ghost Admin under Settings → Membership → Tips & donations until the upgrade is applied. ### References Ghost thanks sane100400 and [p4p3r](https://hackerone.com/p4p3r_hak) for disclosing this vulnerability responsibly. ### For more information If you have any questions or comments about this advisory, email Ghost at [security@ghost.org](mailto:security@ghost.org).

CVE-2026-59817 Affected Ghost Versions

1 component(s)
Fixed Versions:
6.44.0
Product / Package Ecosystem Affected Versions Fixed Version
ghost
npm/ghost
npm
≥ 6.27.0
< 6.44.0
6.44.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/TryGhost/Ghost/security/advisories/GHSA-xm43-3m56-w3wf
NVD — CVE-2026-59817 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59817
Ghost Source Repository REPOSITORY
https://github.com/TryGhost/Ghost/pull/28351
Ghost Source Repository REPOSITORY
https://github.com/TryGhost/Ghost/pull/28352
Security Fix Commit FIX COMMIT
https://github.com/TryGhost/Ghost/commit/cab716cd015ac04b7ee50c7a405478d97bc7b1e0
Security Fix Commit FIX COMMIT
https://github.com/TryGhost/Ghost/commit/ee7b991b466a7849c70f9d1caed8e491ee4113c6
Ghost Source Repository REPOSITORY
https://github.com/TryGhost/Ghost

Frequently Asked Questions

What is CVE-2026-59817?
CVE-2026-59817 is a security vulnerability in Ghost involving Paid gift memberships obtainable at minimal cost via the donations feature under CWE-639: Authorization Bypass Through User-Controlled Key.
Which Ghost versions are affected?
Affected versions include releases prior to 6.44.0 across affected packages: ghost.
What version fixes CVE-2026-59817?
Upgrading to 6.44.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ghost affected?
Yes, ghost is affected in releases prior to 6.44.0. Upgrade your dependency to 6.44.0 or later.
What is the CVSS score of CVE-2026-59817?
CVE-2026-59817 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
What CWE is associated with CVE-2026-59817?
CVE-2026-59817 is classified under CWE-639: Authorization Bypass Through User-Controlled Key (The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.).
How can I check npm dependencies for CVE-2026-59817?
Run the dependency tree command: 'npm ls ghost'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-xm43-3m56-w3wf",
  "modified" : "2026-08-04T21:57:48Z",
  "published" : "2026-08-04T21:57:48Z",
  "aliases" : [ "CVE-2026-59817" ],
  "summary" : "Ghost: Paid gift memberships obtainable at minimal cost via the donations feature",
  "details" : "### Impact\n\nA vulnerability in Ghost's public donation checkout flow allowed an unauthenticated attacker to obtain full paid gift memberships for a minimal payment. No customer or member data was exposed, and the issue could not be used to steal money from a site or its members.\n\n### Vulnerable versions\n\nThis vulnerability is present in Ghost from [v6.27.0](https://github.com/TryGhost/Ghost/releases/tag/v6.27.0) up to [v6.43.1](https://github.com/TryGhost/Ghost/releases/tag/v6.43.1).\n\n### Patches\n\n[v6.44.0](https://github.com/TryGhost/Ghost/releases/tag/v6.44.0) contains a fix for this issue. \n\n### How to update\n\nFor self-hosters using Docker, find [Docker’s official Ghost image on Docker Hub](https://hub.docker.com/_/ghost) and follow the documentation on [updating a Docker-based Ghost instance](https://docs.ghost.org/install/docker#updating-ghost).\n\nFor self-hosters using Ghost-CLI, see the documentation for [updating Ghost to the latest version](https://docs.ghost.org/update).\n\n### Workarounds\n\nIf upgrading immediately is not possible, you can remove the vulnerable checkout path by disabling the donations feature in Ghost Admin under Settings → Membership → Tips & donations until the upgrade is applied.\n\n### References\n\nGhost thanks sane100400 and [p4p3r](https://hackerone.com/p4p3r_hak) for disclosing this vulnerability responsibly.\n\n### For more information\n\nIf you have any questions or comments about this advisory, email Ghost at [security@ghost.org](mailto:security@ghost.org).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "ghost"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.27.0"
      }, {
        "fixed" : "6.44.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/TryGhost/Ghost/security/advisories/GHSA-xm43-3m56-w3wf"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-59817"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/TryGhost/Ghost/pull/28351"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/TryGhost/Ghost/pull/28352"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/TryGhost/Ghost/commit/cab716cd015ac04b7ee50c7a405478d97bc7b1e0"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/TryGhost/Ghost/commit/ee7b991b466a7849c70f9d1caed8e491ee4113c6"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/TryGhost/Ghost"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-472", "CWE-639" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-04T21:57:48Z",
    "nvd_published_at" : "2026-07-09T18:16:57Z"
  }
}