Ghost Content API filter bypass reveals private fields

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Ghost is a Node.js content management system. From 5.46.1 until 6.21.2, the validation applied to filters on the public API endpoints could be partially bypassed, making it possible to reveal private fields via a brute force attack. If SQLite was used as the database password hashes were fully accessible. If MySQL was used as the database the password hashes' case (uppercase / lowercase) would have been lost, which would likely have rendered a further brute force attack on the discovered hashes fruitless. This vulnerability is fixed in 6.21.2.

Source published

24 Jun 2026 18:05:29 UTC

Source modified

24 Jun 2026 18:55:24 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Ghost is a Node.js content management system. From 5.46.1 until 6.21.2, the validation applied to filters on the public API endpoints could be partially bypassed, making it possible to reveal private fields via a brute force attack. If SQLite was used as the database password hashes were fully accessible. If MySQL was used as the database the password hashes' case (uppercase / lowercase) would have been lost, which would likely have rendered a further brute force attack on the discovered hashes fruitless. This vulnerability is fixed in 6.21.2.

Source published

Jun 24, 2026, 6:05:29 PM (timezone not stated)

Source modified

Jun 24, 2026, 6:55:24 PM (timezone not stated)

Observed here

7 Nov 2026 12:28:05 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Ghost is a Node.js content management system. From 5.46.1 until 6.21.2, the validation applied to filters on the public API endpoints could be partially bypassed, making it possible to reveal private fields via a brute force attack. If SQLite was used as the database password hashes were fully accessible. If MySQL was used as the database the password hashes' case (uppercase / lowercase) would have been lost, which would likely have rendered a further brute force attack on the discovered hashes fruitless. This vulnerability is fixed in 6.21.2.

Source published

24 Jun 2026 19:17:12 UTC

Source modified

25 Oct 2026 22:10:00 UTC

Observed here

27 Oct 2026 14:13:29 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

### Impact The validation applied to filters on the public API endpoints could be partially bypassed, making it possible to reveal private fields via a brute force attack. If SQLite was used as the database password hashes were fully accessible. If MySQL was used as the database the password hashes' case (uppercase / lowercase) would have been lost, which would likely have rendered a further brute force attack on the discovered hashes fruitless. ### Vulnerable versions This vulnerability is present in Ghost from v5.46.1 up to v6.21.1. ### Patches v6.21.2 contains a fix for this issue. ### How to update For self-hosters using Docker, find [Docker's official Ghost image here](https://hub.docker.com/_/ghost). Updating a Docker-based Ghost instance [is documented here](https://docs.ghost.org/install/docker#updating-ghost). If your Ghost is a Ghost-CLI install see our documentation on [updating it to the latest version here](https://docs.ghost.org/update). ### Workarounds If upgrading immediately is not possible, block or filter requests to Content API endpoints where the `filter` query parameter contains `password` or `email` (including any compound form such as `users.password`, `users.email`, `authors.password`, `authors.email`). Reject requests at a reverse proxy / WAF layer before they reach Ghost. Example (case-insensitive) pattern to block on the raw querystring: ``` filter=[^&]*(password|email) ``` ### References Ghost thanks crnkovic for disclosing this vulnerability responsibly. ### For more information If you have any questions or comments about this advisory, email Ghost at [[email protected]](mailto:[email protected]).

Source published

5 Aug 2026 14:42:47 UTC

Source modified

5 Aug 2026 14:45:20 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Publisher rating · MODERATE