CVE-2026-54002
High
Description
Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites and plugins that use the writer or list fields or call Dom::sanitize(), Sane::sanitize(), Sane::Html::sanitize(), Sane::Svg::sanitize(), Sane::Xml::sanitize(), Sane::sanitizeFile(), or file sanitizeContents() with untrusted input allow malicious markup injected as children of an unknown HTML or XML tag to pass through Dom::sanitize() without being correctly sanitized, causing stored cross-site scripting. This issue is fixed in versions 4.9.4 and 5.4.4.
SeverityHigh
CVSS8.5
Exploit probability—
ProductGetkirby/cms
PublishedJul 9, 2026
First seenJul 9, 2026
Weakness typeCWE-79Cross-site scripting (XSS)CWE-87CWE-87
How to fix
Update
- getkirby/cms4.9.4, 5.4.4 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| getkirby/cmsPackagist | v < 4.9.4, 5.0.0-alpha.1 ≤ v < 5.4.4 | 4.9.4, 5.4.4 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.