CVE-2026-53943 json
Ghost: Cache-poisoning XSS in Ghost frontend via x-ghost-preview header
published 4mo ago modified 17d ago also BIT-ghost-2026-53943 , EUVD-2026-39027 , GHSA-62q6-4hv4-vjrw
- cvss
- 9.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 39%
- public exploits
- 0
- none known
Summary
Ghost is a Node.js content management system. From until 6.37.0, when Ghost is behind a shared caching layer that results in cached content being shared between different visitors, an unauthenticated user could send an x-ghost-preview header that altered the rendered frontend response. In affected cache configurations, that response could be stored and served to subsequent visitors requesting the same page, allowing cache poisoning of request-specific preview output. When running Ghost's frontend and admin panel on the same domain this could be used to take over staff user accounts. When running these on different domains staff accounts have no exposure. This vulnerability is fixed in 6.37.0.
Patch / fix
- npm ghost 6.37.0
- bitnami ghost 6.37.0
- ghost ghost 6.37.0
Is CVE-2026-53943 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 4mo ago
Exploit prediction
0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
| GitHub | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
| OSV | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | ghost | >=4.0.0, <6.37.0 |
6.37.0 |
| bitnami | ghost | >=4.0.0, <6.37.0 |
6.37.0 |
Affected products
- TryGhost Ghost
Classification
- Weakness
-
- CWE-524 Use of Cache Containing Sensitive Information
References
Sources
- CVE List CVE-2026-53943
- GitHub Advisory GHSA-62q6-4hv4-vjrw
- NVD CVE-2026-53943
- OSV BIT-ghost-2026-53943
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.