GHSA-xm43-3m56-w3wf BIT-ghost-2026-59817 CVE-2026-59817
Ghost: Paid gift memberships obtainable at minimal cost via the donations feature
- Severity
- 5.3 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.40%
- Chance of exploitation in the next 30 days. Higher than 34.55% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-472 External Control of Assumed-Immutable Web Parameter
- CWE-639 Authorization Bypass Through User-Controlled Key
- Fix
6.44.0- Upgrade ghost to this version or later
Description
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 up to v6.43.1.
Patches
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 and follow the documentation on updating a Docker-based Ghost instance.
For self-hosters using Ghost-CLI, see the documentation for updating Ghost to the latest version.
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 for disclosing this vulnerability responsibly.
For more information
If you have any questions or comments about this advisory, email Ghost at security@ghost.org.
Affected versions
npm
| Package | Vulnerable | Fixed in |
|---|---|---|
| ghost | >= 6.27.0, < 6.44.0 |
6.44.0 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
ghost npm → 6.44.0
- npm
npm install ghost@6.44.0- yarn
yarn add ghost@6.44.0- pnpm
pnpm add ghost@6.44.0
Severity breakdown
CVSS 3.1 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Weakness
CWE-472: External Control of Assumed-Immutable Web Parameter
The web application does not sufficiently verify inputs that are assumed to be immutable but are actually externally controllable, such as hidden form fields.
How to prevent it
- Implementation: Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- Implementation: Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
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 to prevent it
- Architecture and Design: For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Architecture and Design, Implementation: Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Architecture and Design: Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-x3mg-q38v-m562 Ghost: Authorization Issue Allowed Author Role to Delete any Post | Medium | Also affects ghost |
| GHSA-8575-cr6v-7jh4 Ghost: Stored XSS via SVG Uploads Bypassing Sanitization | High | Also affects ghost |
| GHSA-r7f2-6fj8-6fg2 Ghost: Private IP Filtering Bypass via IPv6 Transition Addresses | Medium | Also affects ghost |
| GHSA-322m-ff4g-9vx9 Ghost: Server-Side Request Forgery in Bookmark Fetching | Medium | Also affects ghost |
| GHSA-fwh9-qg68-vxp4 Ghost: Regular Expression Denial of Service in Content Import | Medium | Also affects ghost |
| GHSA-9m4w-fmjw-fvjq Ghost: Regular Expression Denial of Service in External Media Inliner | Medium | Also affects ghost |
| GHSA-hqq2-xqr2-fmx2 Ghost : Stored XSS via SVG Files in Content Imports | Medium | Also affects ghost |
| GHSA-69qc-f5m6-889c Ghost: Stored XSS via Embed Card Previews | High | Also affects ghost |
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