CVE-2026-42137: Kirby: `pages.access/list` and `files.access/list` permissions are not consistently checked in the REST API and changes dialog

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-09 · updated 2026-07-24
Weakness: CWE-862

Description

Kirby is an open-source content management system. Prior to versions 4.9.0 and 5.4.0, `pages.access/list` and `files.access/list` permissions are not consistently checked in the Panel and REST API. This issue has been patched in versions 4.9.0 and 5.4.0.

Affected products

getkirby kirby: before 4.9.0; from 5.0.0 before 5.4.0 — fixed in 4.9.0, 5.4.0

How to fix

Upgrade to a fixed version: getkirby kirby 4.9.0, 5.4.0. Check the vendor advisory for mitigations.

References

https://github.com/getkirby/kirby/releases/tag/4.9.0
https://github.com/getkirby/kirby/releases/tag/5.4.0
https://github.com/getkirby/kirby/security/advisories/GHSA-85x2-r8xv-ww8c

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