Cross-site scripting in Kirby - #VU150666
Published: September 17, 2026
Vulnerability identifier: #VU150666
CSH Severity: Low
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: N/A
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary scripts in the browsers of site visitors and logged-in users.
The vulnerability exists due to improper neutralization of imported HTML in Kirby\'s HTML importer for blocks when importing HTML into blocks or layout fields. A remote user can paste crafted table or non-video iframe HTML into an updatable field to execute arbitrary scripts in the browsers of site visitors and logged-in users.
The Panel does not render imported block content as HTML.
Affected software
Kirby
Remediation
Install security update from vendor's website.
Kirby - addressed in versions 4.9.6, 5.6.0