Description
Kirby is an open-source content management system. In versions prior to 4.9.1 and 5.4.1, Kirby did not securely sanitize the contents of the list field on save, leaving it vulnerable to cross-site scripting (XSS). Kirby's list field stores its formatted content as HTML, and unlike other field types, its HTML special characters cannot be escaped without losing the formatting. Sanitization was only enforced client-side in the Panel, while the server did not sanitize the content on save. As a result, an attacker could bypass the Panel and send malicious HTML directly to Kirby's API, storing unsanitized markup in the content file. That markup would then be rendered on the site frontend and executed in the browsers of site visitors and logged-in users browsing the site, resulting in persistent XSS. This issue has been fixed in versions 4.9.1 and 5.4.1.
Published: 2026-07-16
Score: 8.5 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-5fhx-9q32-q257 Kirby CMS vulnerable to cross-site scripting (XSS) from list field content in the site frontend
History

Thu, 16 Jul 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Getkirby
Getkirby kirby
Vendors & Products Getkirby
Getkirby kirby

Thu, 16 Jul 2026 21:45:00 +0000

Type Values Removed Values Added
Description Kirby is an open-source content management system. In versions prior to 4.9.1 and 5.4.1, Kirby did not securely sanitize the contents of the list field on save, leaving it vulnerable to cross-site scripting (XSS). Kirby's list field stores its formatted content as HTML, and unlike other field types, its HTML special characters cannot be escaped without losing the formatting. Sanitization was only enforced client-side in the Panel, while the server did not sanitize the content on save. As a result, an attacker could bypass the Panel and send malicious HTML directly to Kirby's API, storing unsanitized markup in the content file. That markup would then be rendered on the site frontend and executed in the browsers of site visitors and logged-in users browsing the site, resulting in persistent XSS. This issue has been fixed in versions 4.9.1 and 5.4.1.
Title Kirby: Cross-site scripting (XSS) from list field content in the site frontend
Weaknesses CWE-79
References
Metrics cvssV4_0

{'score': 8.5, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-16T21:36:06.390Z

Reserved: 2026-05-05T14:39:34.923Z

Link: CVE-2026-44175

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-16T22:30:06Z

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')