CVE-2026-42842 json
grav-plugin-form: XSS via Taxonomy Field Values in Admin Panel
published 2026-05-05 6 mo ago modified 2026-10-26 13 d ago also GHSA-c2q3-p4jr-c55f , EUVD-2026-29127
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 7%
- public exploits
- 0
- none known
Summary
The form plugin for Grav adds the ability to create and use forms. Prior to 9.1.0, a Stored Cross-Site Scripting (XSS) vulnerability exists in the Grav CMS Form plugin's select field template. Taxonomy tag and category values are rendered with the Twig |raw filter in the admin panel, bypassing the global autoescape protection. An editor-level user can inject arbitrary JavaScript that executes in any administrator's browser session when they view or edit any page in the admin panel. This vulnerability is fixed in 9.1.0.
Patch / fix
- packagist getgrav/grav 2.0.0-beta.2
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5 mo ago
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/getgrav/grav/security/advisories/GHSA-c2q3-p4jr-c55f referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| GitHub | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | getgrav/grav | <2.0.0-beta.2 |
2.0.0-beta.2 |
Affected products
- getgrav grav
- getgrav grav-plugin-form
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/getgrav/grav-plugin-form/commit/6bffb4c98be468a155d1656544ec45bb4a443957
web
-
github.com
/getgrav/grav/commit/5a12f9be8314682c8713e569e330f11805d0a663
web
-
github.com
/getgrav/grav/security/advisories/GHSA-c2q3-p4jr-c55f
exploit, web
-
nvd.nist.gov
/vuln/detail/CVE-2026-42842
advisory
-
github.com
/getgrav/grav
package
Sources
- CVE List CVE-2026-42842
- GitHub Advisory GHSA-c2q3-p4jr-c55f
- NVD CVE-2026-42842
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