CVE-2026-44175
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.
What this means
- Exposure
- Exploitable remotely over the network and with an ordinary user account — but only if a user opens booby-trapped content.
- Impact
- An attacker can read sensitive data and modify or destroy data.
- Weakness
- Attacker-supplied script runs in other users’ browsers (cross-site scripting).
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doFold into the next patch cycle.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.