Stored cross-site scripting in GutenKit via page custom CSS
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-79.
Summary
The GutenKit WordPress plugin from 2.5.0 before 2.5.5 does not sanitize custom CSS saved against a post before printing it inside an inline style block (CWE-79). An author or higher role can break out of the style element and store JavaScript that runs in the browser of any visitor who views the post. An exploit link is listed in the references.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
The GutenKit WordPress plugin before 2.5.5 does not properly sanitize custom CSS saved against a post before printing it inside an inline style block on the published page, allowing users with the Author role and above to break out of the style element and store JavaScript that executes in the browser of any visitor who views the post. Exploitation affects sites running WordPress below 7.0.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Unknown | GutenKit | 2.5.0 to before 2.5.5 | 2.5.5 | Patch available | CNA |
- GutenKit VendorUnknown Affected 2.5.0 to before 2.5.5 Fixed in 2.5.5 Patch available CNA
Remediation
Update GutenKit to version 2.5.5.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA GutenKit (Unknown) Fixed in 2.5.5
Timeline
- 2026-11-06 Threatist record created from CVE-2026-114427
- 2026-11-06 Alias added: GHSA-jqp9-9h3q-mgjq
- 2026-11-06 CVSS score added · CISA ADP
- 2026-11-06 Weakness changed · CISA ADP
- 2026-11-06 CISA SSVC decision points changed
References
Sources
- CVE-2026-114427 · CVE Program
- CVE-2026-114427 · NVD
- FIRST EPSS
- GHSA-jqp9-9h3q-mgjq · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences