Vulnerability Description
Kirby is an open-source content management system. In versions prior to 4.9.1 and 5.4.1, the underlying URL methods for the KirbyTags and image blocks components did not filter out malicious URL values that resolve to script execution. The vulnerability affects four first-party Kirby renderers that produce `<a href="…">` output from editor-supplied field values: the (`link: …)` KirbyTag, the `link`: parameter of the `(image: …)` KirbyTag when it does not resolve to a known file or `self`, the `link` field of the built-in image block, and the HTML importer for the `blocks` field (which accepted the same malicious input as the image block `link` field). While simple `avascript:` URLs were already deactivated by treating them as a relative path and prepending a single slash to the URL, the use of URLs of the format `javascript://x%0A…` bypasses this protection. The `vbscript:`, `data:`, `livescript:`, `mocha:` and `jar:` schemes are affected by the same underlying gap. This issue has been fixed in versions 4.9.1 and 5.4.1.
Related Weaknesses (CWE)
References
- https://github.com/getkirby/kirby/releases/tag/5.4.1
- https://github.com/getkirby/kirby/security/advisories/GHSA-qvjf-922g-pj44
FAQ
What is CVE-2026-45368?
CVE-2026-45368 is a documented vulnerability. Kirby is an open-source content management system. In versions prior to 4.9.1 and 5.4.1, the underlying URL methods for the KirbyTags and image blocks components did not filter out malicious URL value...
How severe is CVE-2026-45368?
CVSS scoring is not yet available for CVE-2026-45368. Check NVD for updates.
Is there a patch for CVE-2026-45368?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.